Blocking properties of terguride at the 5-HT2 receptor subtypes mediating cardiovascular responses in the rat

2020 ◽  
Vol 98 (8) ◽  
pp. 511-521
Author(s):  
Oscar Alcántara-Vázquez ◽  
Ma. Trinidad Villamil-Hernández ◽  
Araceli Sánchez-López ◽  
Heinz H. Pertz ◽  
Carlos M. Villalón ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Diastolic Blood Pressure ◽  
Receptor Agonist ◽  
Cardiovascular Responses ◽  
Receptor Subtypes ◽  
Pithed Rats ◽  
Anaesthetized Rats ◽  
Dose Dependent

In vitro studies have suggested that terguride blocks the contractile and relaxant responses produced by 5-hydroxytryptamine (5-HT) via 5-HT2A/2B receptors. This study has now investigated terguride’s blocking properties on central/peripheral 5-HT2 receptors in anaesthetized or pithed rats. Male Wistar anaesthetized/pithed rats were cannulated for recording blood pressure and heart rate and for i.v. administration of several compounds. In both groups of rats, i.v. bolus injections of 5-HT or (±)-DOI (a 5-HT2 receptor agonist; 1–1000 μg/kg) produced dose-dependent increases in diastolic blood pressure and heart rate. These responses were dose-dependently antagonized by terguride (10–3000 μg/kg). In anaesthetized rats, i.v. bolus injections of BW723C86 (a 5-HT2B receptor agonist; 1–1000 μg/kg) produced dose-dependent increases in diastolic blood pressure and not dose-dependent increases in heart rate, while in pithed rats, these responses were attenuated. The vasopressor responses elicited by BW723C86 in anaesthetized rats were dose-dependently blocked by terguride (10–300 μg/kg), whereas its the tachycardic responses were dose-independently blocked. These results, taken together, suggest that terguride behaved as an antagonist at the 5-HT2 receptors located in the central nervous system and (or) the systemic vasculature. This is the first evidence demonstrating that terguride can block central/peripheral 5-HT2 receptors mediating cardiovascular responses in anaesthetized or pithed rats.

Power Spectral Analysis of Heart Rate and Diastolic Blood Pressure Variability in Migraine with and Without Aura

Cephalalgia ◽  
1997 ◽  
Vol 17 (7) ◽  
pp. 756-760 ◽  
Author(s):  
G Pierangeli ◽  
P Parchi ◽  
G Barletta ◽  
M Chiogna ◽  
E Lugaresi ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Spectral Analysis ◽  
Diastolic Blood Pressure ◽  
Blood Pressure Variability ◽  
Power Spectral Analysis ◽  
Cardiovascular Responses ◽  
Valsalva Manoeuvre ◽  
Cardiovascular Reflexes ◽  
Power Spectral

Autonomic function in migraineurs during headache-free periods was studied by means of cardiovascular reflexes and power spectral analysis of heart rate and diastolic blood pressure variability. We examined 56 patients: 37 suffering from migraine without aura and 19 from migraine with aura. Cardiovascular responses to the tilt test and Valsalva manoeuvre showed a normal function of the overall baroreceptor reflex arc. Normal heart rate responses to valsalva manoeuvre and deep breathing suggested an intact parasympathetic function. Power spectral analysis of both heart rate and diastolic blood pressure variability in basal conditions and during orthostatic test showed similar sympathovagal interactions modulating cardiovascular control in migraine patients and in controls.

What role do adrenoreceptor polymorphisms play in modifying cardiovascular responses in obstructive sleep apnoea?

2005 ◽  
Vol 110 (1) ◽  
pp. 89-91 ◽  
Author(s):  
Nigel Mcardle
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular Risk ◽  
Diastolic Blood Pressure ◽  
Obstructive Sleep Apnoea ◽  
Cardiovascular Responses ◽  
Sleep Apnoea ◽  
Cpap Treatment ◽  
Obstructive Sleep

OSA (obstructive sleep apnoea) is a common condition that is strongly associated with cardiovascular disease. It is remains unclear what role OSA plays in determining cardiovascular risk. The immediate physiological changes that occur during upper airway obstruction are potential contributors to cardiovascular risk in OSA. These changes include increased sympathetic activity, which is responsive to treatment of OSA with CPAP (continuous positive airway pressure). In this issue of Clinical Science, the possible role of a common polymorphism in the β1-adrenoreceptor [R389G (Arg389Gly)] has been investigated by Börgel and co-workers. Measurements of heart rate and blood pressure in untreated OSA patients were not related to the R389G polymorphism. There were changes in heart rate and diastolic blood pressure with CPAP treatment that were related to this polymorphism. Reduction in heart rate with CPAP treatment was associated with the R389R genotype. By contrast, a reduction in diastolic blood pressure was associated with the Gly389 carriers. These findings are intriguing, but difficult to fully explain. Further study is needed to determine if there is an important role of the R389G polymorphism in modifying cardiovascular responses among OSA patients.

Is Substance P the Transmitter at the First Synapse of the Baroreceptor Reflex in Rats and Cats?

1980 ◽  
Vol 59 (s6) ◽  
pp. 295s-297s ◽  
Author(s):  
G. Haeusler ◽  
R. Osterwalder
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Substance P ◽  
Cardiovascular Effects ◽  
Baroreceptor Reflex ◽  
Solitary Tract ◽  
Anaesthetized Rats ◽  
Contrast Exposure ◽  
Brain Ventricle ◽  
Dose Dependent

1. Substance P, injected into a lateral brain ventricle of urethane-anaesthetized rats, caused dose-dependent increases in blood pressure and heart rate. 2. By contrast, exposure of the obex region of the medulla oblongata to pieces of filter paper soaked in substance P-containing solution resulted in falls of blood pressure and heart rate in both rats and cats. 3. A more precise application of substance P to the first synapse of the baroreceptor reflex by micro-injection into defined areas of the nucleus of the solitary tract also led to an activation of the baroreceptor reflex. 4. Capsaicin, which is known to release substance P from primary afferents, mimicked the sympatho-inhibitory and cardiovascular effects of substance P when applied locally to the nucleus of the solitary tract. 5. The results are compatible with a transmitter or neuromodulatory role for substance P at the first synapse of the baroreceptor reflex.

scholarly journals Reflex cardiovascular responses originating in exercising muscles of mice

2001 ◽  
Vol 90 (2) ◽  
pp. 579-585 ◽  
Author(s):  
Jeffery M. Kramer ◽  
Arthur Aragones ◽  
Tony G. Waldrop
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Muscle Contraction ◽  
Cardiovascular Responses ◽  
Muscular Contraction ◽  
Dependent Manner ◽  
Direct Stimulation ◽  
Systemic Hypoxia ◽  
Dose Dependent ◽  
Stimulation Of

The cardiovascular responses induced by exercise are initiated by two primary mechanisms: central command and reflexes originating in exercising muscles. Although our understanding of cardiovascular responses to exercise in mice is progressing, a murine model of cardiovascular responses to muscle contraction has not been developed. Therefore, the purpose of this study was to characterize the cardiovascular responses to muscular contraction in anesthetized mice. The results of this study indicate that mice demonstrate significant increases in blood pressure (13.8 ± 1.9 mmHg) and heart rate (33.5 ± 11.9 beats/min) to muscle contraction in a contraction-intensity-dependent manner. Mice also demonstrate 23.1 ± 3.5, 20.9 ± 4.0, 21.7 ± 2.6, and 25.8 ± 3.0 mmHg increases in blood pressure to direct stimulation of tibial, peroneal, sural, and sciatic hindlimb somatic nerves, respectively. Systemic hypoxia (10% O2-90% N2) elicits increases in blood pressure (11.7 ± 2.6 mmHg) and heart rate (42.7 ± 13.9 beats/min), while increasing arterial pressure with phenylephrine decreases heart rate in a dose-dependent manner. The results from this study demonstrate the feasibility of using mice to study neural regulation of cardiovascular function during a variety of autonomic stimuli, including exercise-related drives such as muscle contraction.

Alteration of adrenergic responses by chronic cholinergic blockade

1960 ◽  
Vol 199 (1) ◽  
pp. 117-123
Author(s):  
David C. Jerram
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Diastolic Blood Pressure ◽  
Peripheral Resistance ◽  
Submaxillary Gland ◽  
Chronic Administration ◽  
Cardiovascular Responses ◽  
Adrenergic Agents ◽  
Cholinergic Blockade

The effect of the chronic administration of cholinergic blocking agents on the secretory and cardiovascular responses to epinephrine, levarterenol and isoproterenol has been determined in the dog. Chronic cholinergic blockade (CCB) produced a supersensitivity of the submaxillary gland to epinephrine and levarterenol as has been shown previously. Isoproterenol was found to have a profound secretory effect on the submaxillary gland of the dog. During CCB, the volume of secretion produced by isoproterenol was greatly increased. Changes in systolic and diastolic blood pressure, cardiac output, peripheral resistance, heart rate and duration of systole produced by graded doses of epinephrine, levarterenol and isoproterenol were not significantly or systematically altered by CCB. It was concluded that CCB does not alter the sensitivity of the vasculature to adrenergic agents. In 12 of 13 dogs, the heart rate after acute atropinization was significantly lower during CCB than in the control experiments.

scholarly journals The Effects of Music Intensity on Performance and Cardiovascular Responses in Athletes

2020 ◽  
Vol 12 (1) ◽  
pp. 225-232
Author(s):  
Paria Torkamandi ◽  
◽  
Ali Akbarnejad ◽  
Abbas Ali Gaeini ◽  
Ali Gharecheshmei Ghahremanloo ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Oxygen Consumption ◽  
Diastolic Blood Pressure ◽  
Cardiovascular Responses ◽  
Time To Exhaustion ◽  
Maximum Oxygen Consumption ◽  
Maximum Heart Rate ◽  
Male Athletes ◽  
Pressure Maximum

Introduction: The current study aimed to evaluate the effects of different musical intensities on performance and cardiovascular responses after incremental exercise in male athletes. Materials and Methods: In this quasi-experimental study with a cross-over design, 15 male athletes were voluntarily selected. The study subjects performed Bruce protocol, along with listening to progressive music, slow music, and without music until exhaustion. Results: This study indicated that systolic and diastolic blood pressure, maximum oxygen consumption, maximum heart rate, and time to exhaustion insignificantly decreased while listening to slow music, compared to the no music (P=0.134, P=0.993, P=0.999, P=0.160, P=0.819, respectively). Furthermore, while listening to progressive music, compared to no music, the systolic and diastolic blood pressure, as well as maximum heart rate insignificantly increased (P=0.735, P=0.999, P=0.496, respectively); the maximum oxygen consumption and the time of exhaustion significantly increased in the study subjects (P=0.043, P=0.008 respectively). Moreover, while listening to progressive music, compared to slow music, the systolic blood pressure, maximum oxygen consumption, maximum heart rate, and the time of exhaustion significantly increased (P=0.004, P=0.009, P=0.002, P=0.001 respectively); however, diastolic blood pressure presented an insignificant decrease (P=0.253). Conclusion: The obtained findings revealed that listening to progressive music can affect physiological factors and performance during exercising. It increases the athlete’s motivation and postpones the time to exhaustion to continue exercising; however, listening to slow music creates a state of relaxation during exercise and reduces heart rate. As a result, individuals with hypertension can decline their blood pressure during endurance exercise by listening to soft music.

Cardiovascular Variability and Reactivity in Major Depressive Disorder

2021 ◽  
pp. 1-14
Author(s):  
Stefan Duschek ◽  
Angela Bair ◽  
Alexandra Hoffmann ◽  
Josef Marksteiner ◽  
Casandra I. Montoro ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Major Depressive Disorder ◽  
Depressive Disorder ◽  
Diastolic Blood Pressure ◽  
Blood Pressure Variability ◽  
Cardiovascular Responses ◽  
Major Depressive ◽  
Cardiovascular Variability

Abstract. This study investigated cardiovascular variability and stress reactivity in major depressive disorder (MDD). While previous research has documented reduced heart rate variability, knowledge about blood pressure variability in MDD remains scarce. Regarding reactivity, a particular focus was placed on the time courses of the cardiovascular responses, which may provide insight into the autonomic mechanisms underlying the hypo-reactivity expected in MDD. In 76 MDD patients and 71 healthy controls, blood pressure was continuously recorded at rest and during mental stress induced by a 3-min serial subtraction task. Compared to controls, patients exhibited lower systolic and diastolic blood pressure, heart rate variability, and systolic and diastolic blood pressure variability. Moreover, smaller stress-related changes in heart rate, systolic and diastolic blood pressure, and sensitivity of the cardiac baroreflex arose in patients. Cardiovascular parameters did not differ between patients using antidepressants and unmedicated patients. According to time-course analysis, reduced hemodynamic modulations in MDD mainly occurred after 50 s of the stress period. Low heart rate variability in MDD reflects deficient top-down integration of the brain mechanisms allowing flexible autonomic and behavioral control; diminished blood pressure variability is indicative of poor homeostatic capacity with respect to the regulation of blood pressure and organ perfusion. Moreover, blunted cardiovascular reactivity implies poor adjustment of energetic resources to internal and environmental demands and may be a correlate of deficient motivational dynamics characterizing MDD. While cardiovascular hypo-reactivity in MDD may be mediated by baroreflex and adrenergic mechanisms, the fast-acting parasympathetic system may play a subordinate role.

scholarly journals Pharmacological analysis of the increases in heart rate and diastolic blood pressure produced by (S)-isometheptene and (R)-isometheptene in pithed rats

2017 ◽  
Vol 18 (1) ◽  
Author(s):  
Alejandro Labastida-Ramírez ◽  
Eloísa Rubio-Beltrán ◽  
Oswaldo Hernández-Abreu ◽  
Bruce L. Daugherty ◽  
Antoinette MaassenVanDenBrink ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Diastolic Blood Pressure ◽  
Pharmacological Analysis ◽  
Pithed Rats

The Involvement of Platelets and the Coronary Vasculature in Collagen-Induced Sudden Death in Rabbits

1985 ◽  
Vol 53 (01) ◽  
pp. 070-074 ◽  
Author(s):  
G Mallarkey ◽  
G M Smith
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Platelet Count ◽  
Sudden Death ◽  
Myocardial Ischaemia ◽  
Plasma Levels ◽  
Sodium Citrate ◽  
Plasma Samples ◽  
Calcium Entry Blockers

SummaryThe mechanism of collagen-induced sudden death in rabbits was studied by measuring blood pressure (BP), heart rate, ECG, the continuous platelet count and the plasma levels of thromboxane B2 (TxB2) and 6-keto prostaglandin Fia (6-keto PGF1α). Death was preceded by myocardial ischaemia and a sharp fall in BP which occurred before any fall in platelet count was observed. The calcium entry blockers (CEBs), verapamil, nifedipine and PY 108-068 protected the rabbits from sudden death without any significant effect on the decrease in the platelet count or increase in plasma TxB2 levels. 6-keto PGF1α could not be detected in any plasma samples. Indomethacin and tri-sodium citrate also protected the rabbits but significantly reduced the fall in platelet count and plasma TxB2. In vitro studies on isolated aortae indicated that verapamil non-specifically inhibited vasoconstriction induced by KC1, adrenaline and U46619 (a thromboxane agonist). It is concluded that CEBs physiologically antagonize the vasoconstricting actions of platelet-derived substances and that it is coronary vasoconstriction that is primarily the cause of death.

Vasorelaxant and Antihypertensive Effects of Mentha pulegium L. in Rats: An in vitro and in vivo Approach

2020 ◽  
Vol 20 ◽  
Author(s):  
Mohammed Ajebli ◽  
Mohamed Eddouks
Keyword(s):  
Blood Pressure ◽  
Acute Experiment ◽  
Antihypertensive Activity ◽  
Mentha Pulegium ◽  
In Vitro Experiment ◽  
Arterial Blood ◽  
Dose Dependent ◽  
Ca2 Channels

Aims and objective: The aim of the study was to investigate the effect of aqueous aerial part extract of Mentha pulegium L. (Pennyrile) (MPAE) on arterial pressure parameters in rats. Background: Mentha pulegium is a medicinal plant used to treat hypertension in Morocco. Material and methods: In the current study, MPAE was prepared and its antihypertensive activity was pharmacologically investigated. L-NAME-hypertensive and normotensive rats have received orally MPAE (180 and 300 mg/kg) during six hours for the acute experiment and during seven days for the sub-chronic treatment. Thereafter, systolic, diastolic, mean arterial blood pressure and heart rate were evaluated. While, in the in vitro experiment, isolated denuded and intact thoracic aortic rings were suspended in a tissue bath system and the tension changes were recorded. Results: A fall in blood pressure was observed in L-NAME-induced hypertensive treated with MPAE. The extract also produced a dose-dependent relaxation of aorta pre-contracted with NE and KCl. The study showed that the vasorelaxant ability of MPAE seems to be exerted through the blockage of extracellular Ca2+ entry. Conclusion: The results demonstrate that the extract of pennyrile exhibits antihypertensive activity. In addition, the effect may be, at least in part, due to dilation of blood vessels via blockage of Ca2+ channels.

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