Effect of glucagon on amitriptyline-induced cardiovascular toxicity in rats

The aim of this study was to investigate the effect of glucagon on cardiovascular parameters in anesthetized rat model of tricyclic antidepressant overdose. Toxicity was induced by infusion of amitriptyline 0.94 mg/kg/min until a 40–45% of reduction in mean arterial pressure was observed. Amitriptyline infusion rats were then randomized into three groups. Control group of rats (group 1) received a bolus of 5% dextrose followed by the continuous infusion of dextrose, whereas treatment groups received 1 mg/kg (group 2) or 2 mg/kg (group 3) bolus doses of glucagon followed by continuous infusion (0.1 mg/kg/min) of glucagons for 60 min. Mean arterial pressure, heart rate, and electrocardiogram were recorded. Amitriptyline caused a significant decrease in mean arterial pressure and a prolongation in QRS, yet it did not change the heart rate. High-bolus dose of glucagon (2 mg/kg) followed by glucagon infusion significantly increased mean arterial pressure at 40, 50, and 60 min ( P < 0.05) and shortened the prolonged QRS at 50 and 60 min ( P < 0.05) when compared with control group. There was also a significant increase in heart rate. In conclusion, bolus doses followed by a continuous infusion of glucagon were found to be effective in reversing the hypotension and QRS prolongation in the rat model of amitriptyline toxicity. Further studies are needed to reveal the exact mechanism of the proposed effect.

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Effects of V1- and V2-vasopressin (AVP) antagonists on the pressor, AVP and atrial natriuretic peptide responses to a hypertonic saline infusion in conscious anephric rats

Acta Endocrinologica ◽

10.1530/eje.0.1330127 ◽

1995 ◽

Vol 133 (1) ◽

pp. 127-132 ◽

Cited By ~ 4

Author(s):

Kozo Ota ◽

Tokihisa Kimura ◽

Minoru Inoue ◽

Takeharu Funyu ◽

Masaru Shoji ◽

...

Keyword(s):

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Atrial Natriuretic Peptide ◽

Receptor Antagonist ◽

Hypertonic Saline ◽

Natriuretic Peptide ◽

Plasma Volume ◽

Control Group ◽

Antagonist Group

Ota K, Kimura T, Inoue M, Funyu T, Shoji M, Sato K, Ohta M, Yamamoto T, Abe K, Effects of V1- and V2-vasopressin (AVP) antagonists on the pressor, AVP and atrial natriuretic peptide responses to a hypertonic saline infusion in conscious anephric rats. Eur J Endocrinol 1995;133:127–32. ISSN 0804–4643 To examine the role of vasopressin (AVP) receptors in the regulation of the hemodynamics and release of atrial natriuretic peptide (ANP), and the participation of renal nerve inputs in the osmotic AVP release, hypertonic saline (HS) was infused into conscious, bilaterally nephrectomized rats with nonpeptide, selective antagonists for the V1-receptor or V2-receptor of AVP. In the control group, HS alone increased mean arterial pressure, plasma ANP and AVP, plasma volume and plasma osmolality, and decreased the heart rate. In the V1-receptor antagonist group, an increase in the mean arterial pressure and a decrease in heart rate were completely abolished and an increase in plasma ANP was attenuated. In the V2-receptor antagonist group, increases in mean arterial pressure and plasma ANP and a decrease in heart rate were attenuated. However, the ratio of the changes in heart rate to the changes in mean arterial pressure in the V2-receptor antagonist group is significantly higher than that in the control group. In both experimental groups, increases in plasma AVP, plasma volume and plasma osmolality were not different from those in the control group. These results suggest that a HS-induced increase in mean arterial pressure is mediated by the pressor effect of AVP, mainly through V1-receptors, and that the depressor effect of AVP through V2-receptors may not influence tonically HS-induced hypertension. Moreover, HS-induced increase in plasma ANP is mediated mainly by increases in plasma volume and blood pressure, but may not be affected by a direct action of AVP to the heart. Renal afferent nerve inputs may not have effects on the regulation of osmotic AVP release. Kozo Ota, Second Department of Internal Medicine, Tohoku University School of Medicine, 1-1 Seiryo-cho, Aoba-ku, Sendai 980-77, Japan

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Blunted autonomic response to standing up and head-up tilt in individuals with intellectual disabilities

Journal of Applied Physiology ◽

10.1152/japplphysiol.00328.2020 ◽

2021 ◽

Author(s):

Thessa Irena Maria Hilgenkamp ◽

Elizabeth C. Lefferts ◽

Daniel W. White ◽

Tracy Baynard ◽

Bo Fernhall

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Intellectual Disabilities ◽

Autonomic Response ◽

Control Group ◽

Standing Up ◽

Head Up Tilt ◽

Individuals With Intellectual Disabilities

Previous research suggests individuals with intellectual disabilities (ID) may experience autonomic dysfunction, however this has not been thoroughly investigated. PURPOSE: To compare the autonomic response to standing up (active orthostasis) and head up tilt (passive orthostasis) in individuals with ID to a control group without ID. METHODS: Eighteen individuals with and 18 individuals without ID were instrumented with an ECG-lead and finger-photoplethysmography for continuous heart rate and blood pressure recordings. The active and passive orthostasis protocol consisted of 10 minutes supine rest, 10 minutes standing, 10 minutes supine recovery, 5 minutes head-up tilt at 70 degrees, followed by 10 minutes supine recovery. The last five minutes of each position was used to calculate hemodynamic and autonomic function (time- and frequency-domain heart rate and blood pressure variability measures and baroreflex sensitivity). RESULTS Individuals with ID had higher heart rate during baseline and recovery (p<0.05), and an attenuated hemodynamic (stroke volume, heart rate) and heart rate variability response to active and passive orthostasis (interaction effect p<0.05) compared to individuals without ID. Mean arterial pressure (MAP) was higher in individuals with ID at all timepoints. CONCLUSION Individuals with ID demonstrated altered hemodynamic and autonomic regulation compared to a sex- and age-matched control group, evidenced by a higher mean arterial pressure and a reduced response in parasympathetic modulation to active and passive orthostasis.

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Comparison of Arginine Vasopressin, Terlipressin, or Epinephrine to Correct Hypotension in a Model of Anaphylactic Shock in Anesthetized Brown Norway Rats

Anesthesiology ◽

10.1097/00000542-200604000-00018 ◽

2006 ◽

Vol 104 (4) ◽

pp. 734-741 ◽

Cited By ~ 21

Author(s):

Pascale Dewachter ◽

Valérie Jouan-Hureaux ◽

Isabelle Lartaud ◽

Gaëlle Bello ◽

Nicole de Talancé ◽

...

Keyword(s):

Heart Rate ◽

Mean Arterial Pressure ◽

Confidence Interval ◽

Arterial Pressure ◽

Rat Model ◽

Arginine Vasopressin ◽

Anaphylactic Shock ◽

Brown Norway ◽

Induced Hypotension ◽

Norway Rats

Background Arginine vasopressin (AVP) and terlipressin were proposed as alternatives to catecholamines in shock states characterized by decreased plasma AVP concentrations. The endogenous plasma AVP profile in anaphylactic shock is unknown. In an ovalbumin-sensitized anesthetized anaphylactic shock rat model, the authors investigated (1) plasma AVP concentrations and (2) the dose versus mean arterial pressure response for exogenous AVP and terlipressin and compared them with those of epinephrine. Methods In a first series of rats (n = 12), endogenous plasma AVP concentrations were compared with a model of pharmacologically induced hypotension (nicardipine, n = 12). A second series was randomly assigned to three groups (AVP, n = 7; terlipressin, n = 7; epinephrine, n = 7) and dose (AVP: 8 doses, 0.03-100 U/kg; terlipressin: 7 doses, 0.03-30 microg/kg; epinephrine: 7 doses, 0.3-300 microg/kg)-response mean arterial pressure curves were plotted. Data are expressed as mean +/- SD. Results Endogenous plasma AVP concentrations were significantly lower in anaphylactic shock (57 +/- 26 pg/ml) than in the nicardipine group (91 +/- 43 pg/ml; P < 0.05). The ED50 was 10.6 microg/kg (95% confidence interval, 7.1-15.9) for epinephrine and 4.1 U/kg (95% confidence interval, 3.0-5.6) for AVP. Terlipressin did not change mean arterial pressure, regardless of the dose used. Conclusions In a rat model, anaphylactic shock is associated with inadequately low plasma AVP concentrations. For clinically relevant doses, AVP and epinephrine had comparable effects on mean arterial pressure and heart rate values, whereas, unexpectedly, terlipressin was ineffective. These results are consistent with reports in humans experiencing anaphylaxis where AVP injection restored arterial pressure.

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Comparison of esmolol versus combination of esmolol and fentanyl in preventing cardiovascular stress response to intubation

International Journal of Clinical Trials ◽

10.18203/2349-3259.ijct20170309 ◽

2017 ◽

Vol 4 (1) ◽

pp. 49

Author(s):

Rahul Bhalke ◽

Maroti S. Karale ◽

Umesh Deshmukh

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Stress Response ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Cardiovascular Responses ◽

Intravenous Fentanyl ◽

Group 2 ◽

Post Intubation ◽

Group 1

Background: A number of cardiovascular responses occur during laryngoscopy and intubation which can have serious consequences during anaesthesia.We planned to conduct a study to evaluate effectiveness of intravenous Esmolol and intravenous Fentanyl in attenuating hemodynamic stress response to laryngoscopy and endotracheal intubation.Methods: A prospective, observational, randomized, double blind comparative clinical study, conducted on 60 cases of ASA grade I/II patients undergoing elective abdominal surgery under general anesthesia. The data obtained was divided in the two groups based on drug used 5 min prior to induction, Group 1 (I.V. Esmolol 2 mg/kg) and Group 2 (I.V. Esmolol 2 mg/kg & I.V. Fentanyl 2 µg/kg). Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were measured at various time intervals.Results: There was no significant difference in HR, SBP, DBP, MAP after premedication and induction in both the groups. However at intubation, both groups showed an increase in HR, SBP, DBP and MAP but the rise was attenuated in both groups. Increase in HR was more in group 1 as compared to group 2 and it was statistically significant at 01 and 02 minutes post intubation. The increase in SBP was statistically significant at 00, 01 and 02 minutes post intubation. The increase in MAP was statistically significant immediately after induction, at 00, 01, 02, 05 and 10 minutes post intubation. Conclusions: Combination of intravenous Esmolol and intravenous Fentanyl is more effective in attenuating heart rate, systolic, diastolic and mean arterial pressure response to intubation than intravenous Esmolol alone.

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Changes of Vital Parameters after Administration of Butorphanol during Tiletamine-Zolazepam-Ketamine-Xylazine Anaesthesia for Joint Surgery in Miniature Pigs

Acta Veterinaria Brno ◽

10.2754/avb200877020251 ◽

2008 ◽

Vol 77 (2) ◽

pp. 251-256 ◽

Cited By ~ 6

Author(s):

P. Raušer ◽

L. Lexmaulová ◽

R. Srnec ◽

J. Lorenzová ◽

H. Kecová ◽

...

Keyword(s):

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Physiological Saline ◽

Control Group ◽

Miniature Pigs ◽

Joint Surgery ◽

Vital Functions ◽

End Tidal ◽

Vital Parameters

The study compares the effects of butorphanol in pigs undergoing joint surgery in tiletamine-zolazepam-ketamine-xylazine (TKX) anaesthesia. A total of 12 pigs were divided into 2 groups by 6 animals - BUT (anaesthetized with TKX combination and butorphanol) and CON (control group - anaesthetized with TKX combination only). All pigs were sedated with a mix of tiletamin-zolazepam-ketamin-xylazin, put into total anaesthesia using propofol, and connected to an anaesthesiology unit (O2-Air). For 40 min we logged the heart rate (HR), respiratory rate (RR), mean arterial pressure (MAP), haemoglobin saturation by oxygen (SpO2) and end-tidal CO2 concentration (ETCO2) values. Ten minutes after connecting to the devices, the pigs in the BUT group were intravenously administered butorphanol (0.2 mg/kg) in the total volume of 2 ml, or physiological saline in the same volume. The pigs in the BUT group had a lower (p < 0.05) HR in 5th, 10th and 25th min, and a lower RR in the 10th, 15th and 20th min. MAP, ETCO2 and SpO2 values did not differ substantially. Butorphanol can thus be identified as a suitable analgesic TKX supplement to anaesthesia of miniature pigs with minimum effect on vital functions.

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CARDIOVASCULAR RESPONSE TO LARYNGOSCOPY VERSUS FIBER-OPTIC BRONCHOSCOPE DURING OROTRACHEAL INTUBATION IN PATIENTS UNDERGOING ELECTIVE SURGERY

Pakistan Armed Forces Medical Journal ◽

10.51253/pafmj.v71isuppl-1.2544 ◽

2021 ◽

Vol 71 (Suppl-1) ◽

pp. S180-85

Author(s):

Moazzam Ali ◽

Maliha Khawar ◽

Maryam Nazneen ◽

Zaqawat Nazneen

Keyword(s):

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Fiber Optic ◽

Cardiovascular Response ◽

Macintosh Laryngoscope ◽

Orotracheal Intubation ◽

Control Group ◽

Female Ratio ◽

The Mean

Objective: To compare the hemodynamic response between flexible fiber optic bronchoscope (FOB) andMacintosh laryngoscope during orotracheal intubation. The secondary objective was to calculate the timerequired for intubation between these two techniques Study Design: Quasi experimental study. Place and Duration of Study: Department of Anesthesia, Frontier Corps Hospital Quetta, from Oct 2016 to Apr2017. Methodology: Eighty patients fulfilling the inclusion/exclusion criteria were included in this study and weredivided randomly into two groups. Group L was intubated with Macintosh laryngoscope (control group) whereas group F was intubated with Fiber optic bronchoscope. Mean arterial pressure and heart rate was recorded as baseline, pre-intubation and then every 01 minute for 03 minutes. Changes in heart rate and mean arterial pressure were recorded in the proforma by another anesthetist who was blinded to the procedure performed. Results: The mean age in group L was 41.23 ± 8.37 years and in group F was 40.73 ± 9.77 years. The mean weight in group L was 69.63 ± 8.92 kg and in group F was 70.6 ± 9.20 kg. In group L, male to female ratio was 26:14 whereas in group F it was 28:12. Mean heart rate and mean arterial pressure did not show significant change over time between groups. Time required for intubation was significantly less (22.45 ± 4.12 secs) in laryngoscopy group versus Fiber-Optic Bronchoscope group (44.68 ± 5.88 secs). Conclusion: In conclusion we can say that our study demonstrated that using laryngoscope or Fiber-OpticBronchoscope for orotracheal..........

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Comparison of the Effectiveness of Music Video Therapy and Music Therapy on Pain after Cardiothoracic Surgery in Preschool Children

The Heart Surgery Forum ◽

10.1532/hsf.3509 ◽

2021 ◽

Vol 24 (2) ◽

pp. E299-E304

Author(s):

Ya-li Huang ◽

Yu-qing Lei ◽

Jian-feng Liu ◽

Hua Cao ◽

Xian-rong Yu ◽

...

Keyword(s):

Heart Rate ◽

Preschool Children ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Music Therapy ◽

Hospital Stay ◽

Cardiothoracic Surgery ◽

Music Video ◽

Control Group ◽

Pain Scores

Objective: To explore the effects of music video therapy on pain among preschool children after cardiothoracic surgery. Methods: Patients in the music video therapy (MVT) group received a 30-min music video intervention, while patients in the music therapy (MT) group received a 30-min musical intervention. Both groups were given their respective therapy three times a day for three days. Patients in the control group did not receive MVT or MV. Measures, including pain scores, vital signs (heart rate, mean arterial pressure, respiratory rate, and oxygen saturation), and other postoperative indicators were recorded and analyzed. Results: The MVT group showed a statistically significant decrease in heart rate, mean arterial pressure, and respiratory rate at the first day after surgery and pain scores at the first and second day after surgery compared to the MT group, but no significant difference was identified in oxygen saturation. The postoperative indicators including cumulative capacity of sufentanil use, the length of intensive care unit (ICU) stay, and the length of hospital stay in the MVT group were significantly lower than those in the control group. Conclusion: The findings provide further evidence to support the practice of music video therapy as a non-pharmaceutical intervention to reduce postoperative pain, reduce the dosage of analgesics, shorten the length of ICU and hospital stay in preschool children after the cardiothoracic surgery.

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Effects of the Two Doses of Dexmedetomidine on Sedation, Agitation, and Bleeding During Pediatric Adenotonsillectomy

Anesthesiology and Pain Medicine ◽

10.5812/aapm.118424 ◽

2021 ◽

Vol 11 (5) ◽

Author(s):

Amir Shafa ◽

Hastisadat Aledavud ◽

Hamidreza Shetabi ◽

Sedige Shahhosseini

Keyword(s):

Clinical Trial ◽

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Recovery Room ◽

Pediatric Patients ◽

Sedation Score ◽

Control Group ◽

The Mean ◽

Double Blinded

Background: Due to the importance of dexmedetomidine and its different dosages, here, we aimed to investigate and compare the effectiveness of the doses of 1 µg/kg and 2 µg/kg of dexmedetomidine in sedation, agitation, and bleeding in pediatrics undergoing adenotonsillectomy. Methods: This double-blinded randomized clinical trial was performed on 105 pediatric patients that were candidates for adenotonsillectomy. Then, the patients were divided into three groups receiving dexmedetomidine at a dose of 2 µg/kg, diluted dexmedetomidine at 1 µg/kg, and normal saline. The drugs were administered 15 minutes before operations via the intravenous method. The duration of extubation, mean arterial pressure (MAP), heart rate (HR), and SPO2 in the recovery were recorded. We also collected data regarding patients’ sedation and agitation every 15 minutes. Results: Our data showed no significant differences between the groups of patients regarding MAP, HR, and SPO2. However, the mean sedation score was significantly higher in patients receiving dexmedetomidine (2 µg/kg), and this score was lowest in the control group at the time of entrance to the recovery room. The patients that received dexmedetomidine at a dose of 1 µg/kg had the lowest agitation score after 45 minutes of being in the recovery room, and the patients treated with dexmedetomidine at a dose of 2 µg/kg had the lowest agitation score after 60 minutes of being in the recovery compared to other groups of patients. Conclusions: The use of the doses of 1 µg/kg and 2 µg/kg of dexmedetomidine was associated with proper sedation and a significant reduction in agitation. The patients also had lower amounts of bleeding. We recommend that anesthesiologists should pay more attention to dexmedetomidine at a dose of 2 µg/kg, especially in pediatric surgical procedures.

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Abstract P234: 2-Methoxyestradiol Attenuates Angiotensin II Induced Hypertension: A Novel Paradigm

Hypertension ◽

10.1161/hyp.70.suppl_1.p234 ◽

2017 ◽

Vol 70 (suppl_1) ◽

Author(s):

Yong Zhang ◽

Benard Ogola ◽

Laxmi Iyer ◽

Vardan Karamyan ◽

Thomas Thekkumkara

Keyword(s):

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Heart Weight ◽

Rate Pressure Product ◽

Kidney Cortex ◽

Control Group ◽

Binding Studies ◽

Wky Rats ◽

Induced Hypertension

Estrogen metabolite 2-methoxyestradiol (2ME2) has therapeutic potential in a number of cardiovascular disorders, including hypertension. However, specific or potential targets remains to be determined. In this study, animals were surgically implanted with PA-C40 telemetry in the intra-aortic vessel and 2ME2 (20 mg/kg/day, i.p. injection) effects in AngII infused Wistar-Koyoto (WKY) rats and spontaneously hypertensive rats (SHRs) were determined. In WKY rats 2ME2 treatment resulted in significant reduction in AngII induced blood pressure (BP) compared to vehicle control (systolic; 143.69 ± 2.68 vs. 169.75 ± 1.93 mm Hg, diastolic; 99.91 ± 2.49 vs. 120.16 ± 1.25 mm Hg, and mean arterial pressure; 118.94 ± 2.52 vs. 142.73 ± 1.47 mm Hg). We observed a decrease in heart rate in 2ME2 exposed animals compared to control group (272.67 ± 9.88 vs. 329.12 ± 6.14 BPM). In addition, 2ME2 mediated reduction in workload of the heart when we calculated the rate pressure product or pressure rate index by 13.46 ± 2.32 indicating that 2ME2 can reduce AngII induced hemodynamic stress of the heart. [ 3 H]AngII binding studies showed that in kidney cortex AT1R expression was inhibited by 2ME2 treatment compared to control (2112 ± 71 vs. 3341 ± 248 DPM/mg protein). In a separate 5-week study, 2ME2-treated SHRs displayed significant reduction in diastolic BP (114.31 ± 0.66 vs. 123.28 ± 0.70 mm Hg) and mean arterial pressure (146.35 ± 0.67 vs. 151.54 ± 0.89 mm Hg) without significant change in systolic BP compare to the vehicle treated animals. Moreover, we found significant decrease in heart rate in 2ME2-treated animals (290.03 ± 2.69 vs. 312.92 ± 1.50 BPM). Analyses of kidney cortical tissue revealed downregulation of AT1R expression after 2ME2 treatments (20227 ± 2211 vs. 9515 ± 2115 DPM/mg protein). Consistent with the reduction in BP, the indicators of cardiac hypertrophy including heart weight (1.28 ± 0.08 vs. 0.99 ± 0.02 gram), cardiac collagen deposit and α-smooth muscle actin (α-SMC) positive myofibroblasts were decreased. The data demonstrate for the first time that 2ME2 control BP through downregulation of AT1R in kidney and heart rate, which may provide an insight to the mechanism(s) of cardioprotective effects of 2ME2 through the blockade of AngII induced hypertension.

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Immediate effects of the practise of Sheethali pranayama on heart rate and blood pressure parameters in healthy volunteers

Journal of Complementary and Integrative Medicine ◽

10.1515/jcim-2020-0448 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Rohini P. ◽

Roopa S. ◽

Padmavathi R. ◽

Maheshkumar K.

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Healthy Volunteers ◽

Sympathetic Activity ◽

Pressure Pulse ◽

Control Group ◽

Normal Breathing ◽

And Control

Abstract Objectives Sheetali pranayama, a cooling pranayama is best known for its calming and relaxing nature, widely used for many conditions like depression, anxiety and hypertension. The aim of the study was to evaluate the immediate effect of the practice of Sheetali pranayama on heart rate and blood pressure parameters in healthy volunteers. Methods Apparently, 60 healthy volunteers were involved, from both sexes. They were split into pranayama (n=30) and control (n=30) groups at random. Sheetali pranayama was performed for 5 min (5 cycles) in the pranayama group and normal breathing (12–16 breaths/min) was permitted in the control group. Heart rate (HR) and blood pressure (BP) were recorded with RMS polyrite in the supine position after 5 min of rest. Results The HR in the pranayama group significantly decreased (p=0.04). Systolic (SBP) and diastolic blood (DBP) pressure, pulse pressure (PP) and mean arterial pressure (MAP) decreased significantly (p<0.05) relative to control after pranayama practice. Pre-Post inter-group results has also shown that the pranayama group has substantially decreased HR and BP indices. Conclusions Present study shows that the practice of Sheetlai pranayama creates a relaxed state, and parasympathetic activity overrides sympathetic activity in this state. It indicates that in healthy volunteers, pranayama strengthens the resting cardiovascular parameters.

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