Pituitary and adrenals are required for hyperglycemic reflex initiated by stimulation of CBR with cyanide

1997 ◽  
Vol 272 (1) ◽  
pp. R392-R399 ◽  
Author(s):  
R. Alvarez-Buylla ◽  
E. Alvarez-Buylla ◽  
H. Mendoza ◽  
S. A. Montero ◽  
A. Alvarez-Buylla
Keyword(s):  
Glucose Homeostasis ◽  
Carotid Body ◽  
Sodium Cyanide ◽  
Bilateral Adrenalectomy ◽  
Surgical Removal ◽  
Adrenal Tissue ◽  
Glucose Output ◽  
Arterial Glucose ◽  
Adrenalectomized Rats ◽  
Stimulation Of

We have previously shown that stimulation of carotid body receptors (CBR) with sodium cyanide (NaCN) elicits a rapid hyperglycemic reflex. Here we explore whether the pituitary and adrenals, two glands involved in glucose homeostasis, are necessary for this reflex. Experiments were performed on anesthetized rats that were artificially ventilated. Measurements of hepatic venous-arterial glucose difference indicated that CBR stimulation with a bolus of 5 micrograms/100 g NaCN produced an immediate increase in the output of glucose by the liver. The same dose of NaCN failed to increase hepatic output of glucose in rats with bilateral adrenalectomy or in rats 1 wk after surgical removal of neurohypophysis. Reflex glucose output by the liver was maintained after adenohypophysectomy or in adrenalectomized rats after adrenal autotransplantation to epiploon. Measurements of epinephrine in plasma and in the grafted adrenal tissue showed that the adrenal autograft can store and secrete catecholamines Immunocytochemical observations indicated that the grafted adrenals retain medullary cells. These results indicate that neurohypophysis and adrenals are necessary for the hyperglycemic reflex initiated by CBR stimulation with NaCN and that the participation of these two organs in this reflex is probably humoral.

Vagally mediated insulin secretion by stimulation of brain cholinergic neurons with neostigmine in bilateral adrenalectomized rats

1989 ◽  
Vol 493 (1) ◽  
pp. 97-102 ◽  
Author(s):  
Minehiro Gotoh ◽  
Akihisa Iguchi ◽  
Akira Yatomi ◽  
Kazumasa Uemura ◽  
Hisayuki Miura ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Cholinergic Neurons ◽  
Adrenalectomized Rats ◽  
Stimulation Of

Excitatory amino acid receptors in commissural nucleus of the NTS mediate carotid chemoreceptor responses

1993 ◽  
Vol 264 (1) ◽  
pp. R41-R50 ◽  
Author(s):  
A. Vardhan ◽  
A. Kachroo ◽  
H. N. Sapru
Keyword(s):  
Amino Acid ◽  
Carotid Body ◽  
Excitatory Amino Acid ◽  
Minute Ventilation ◽  
Neuronal Cell ◽  
Excitatory Amino Acid Receptors ◽  
Amino Acid Receptors ◽  
Neuronal Cell Bodies ◽  
Carotid Body Chemoreceptors ◽  
Stimulation Of

Stimulation of carotid body chemoreceptors by saline saturated with 100% CO2 elicited an increase in mean arterial pressure, respiratory rate, tidal volume, and minute ventilation (VE). Microinjections of L-glutamate into a midline area 0.5-0.75 mm caudal and 0.3-0.5 mm deep with respect to the calamus scriptorius increased VE. Histological examination showed that the site was located in the commissural nucleus of the nucleus tractus solitarii (NTS). The presence of excitatory amino acid receptors [N-methyl-D-aspartic acid (NMDA); kainate, quisqualate/alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) and trans 1-amino-cyclopentane-trans-1,3-dicarboxylic acid (ACPD)] in this area was demonstrated by microinjections of appropriate agonists. Simultaneous blockade of NMDA and non-NMDA receptors by combined injections of DL-2-aminophosphonoheptanoate (AP-7; 1 nmol) and 6,7-dinitro-quinoxaline-2,3-dione (DNQX; 1 nmol) abolished the responses to stimulation of carotid body on either side. Combined injections of AP-7 and DNQX did not produce a nonspecific depression of neurons because the responses to another agonist, carbachol, remained unaltered. Inhibition of the neurons in the aforementioned area with microinjections of muscimol (which hyperpolarizes neuronal cell bodies but not fibers of passage) also abolished the responses to subsequent carotid body stimulation on either side.(ABSTRACT TRUNCATED AT 250 WORDS)

Excitatory amino acid receptors within NTS mediate arterial chemoreceptor reflexes in rats

1993 ◽  
Vol 265 (2) ◽  
pp. H770-H773 ◽  
Author(s):  
W. Zhang ◽  
S. W. Mifflin
Keyword(s):  
Electrical Stimulation ◽  
Amino Acid ◽  
Receptor Antagonist ◽  
Carotid Body ◽  
Excitatory Amino Acid ◽  
Pressor Responses ◽  
Carotid Body Chemoreceptors ◽  
Arterial Chemoreceptor ◽  
Stimulation Of ◽  
Arterial Baroreceptor

The nucleus tractus solitarius (NTS) is the primary site of termination of arterial baroreceptor and chemoreceptor afferent fibers. Excitatory amino acid (EAA) receptors within NTS have been shown to play an important role in the mediation of arterial baroreceptor reflexes; however, the importance of EAA receptors within NTS in the mediation of arterial chemoreceptor reflexes remains controversial. Therefore, in chloralose-urethan-anesthetized, mechanically ventilated, paralyzed rats, 4 nmol of the broad-spectrum EAA receptor antagonist kynurenic acid (Kyn) was injected into the NTS to observe the effects of EAA receptor blockade on the pressor responses evoked by either activation of ipsilateral carotid body chemoreceptors (by close arterial injection of CO2-saturated bicarbonate) or electrical stimulation of ipsilateral carotid sinus nerve (CSN). Under control conditions, activation of carotid body chemoreceptors and CSN stimulation evoked increases in arterial pressure of 27 +/- 2 (n = 24 sites) and 28 +/- 3% (n = 8), respectively. Kyn microinjection into NTS significantly reduced the pressor responses evoked by activation of carotid body chemoreceptors and electrical stimulation of the CSN for 20 and 25 min, respectively. Attenuation of pressor responses evoked by chemoreceptor activation were maximal at 20 min post-Kyn injection (13 +/- 2%), whereas CSN-evoked pressor responses were maximally attenuated at 15 min (6 +/- 4%). Microinjection into NTS of 4 nmol of xanthurenic acid, a structural analogue of Kyn with no EAA receptor antagonist properties, had no effect on chemoreceptor reflexes. We conclude that EAA receptors within NTS play an important role in the mediation of arterial chemoreceptor reflexes.

Ovarian carcinoma in a 14-year-old with classical salt-wasting congenital adrenal hyperplasia and bilateral adrenalectomy

2015 ◽  
Vol 28 (5-6) ◽  
Author(s):  
Christian Pina ◽  
Ahmed Khattab ◽  
Philip Katzman ◽  
Lauren Bruckner ◽  
Jeffrey Andolina ◽  
...  
Keyword(s):  
Congenital Adrenal Hyperplasia ◽  
Ovarian Carcinoma ◽  
Left Ovary ◽  
Bilateral Adrenalectomy ◽  
Ca 125 ◽  
Adrenal Hyperplasia ◽  
Serous Adenocarcinoma ◽  
Adrenal Tissue ◽  
Ovarian Serous Adenocarcinoma ◽  
21 Hydroxylase Deficiency

AbstractA 14-year-old female with classical congenital adrenal hyperplasia because of 21-hydroxylase deficiency underwent bilateral adrenalectomy at 6 years of age as a result of poor hormonal control. Because the patient was adrenalectomized, extra adrenal androgen production was suspected. Imaging studies including pelvic ultrasound and pelvic magnetic resonance imaging (MRI) were obtained to evaluate for adrenal rest tumors of the ovaries. Abdominal MRI was obtained to evaluate for residual adrenal tissue. A cystic lesion arising from her right ovary suspicious for ovarian neoplasm was noted on pelvic MRI. Right salpingo-oophorectomy was performed and histopathological examination revealed ovarian serous adenocarcinoma, low-grade, and well-differentiated. Tumor marker CA-125 was elevated and additional ovarian cancer staging workup confirmed stage IIIC due to one lymph node positive for carcinoma. The patient then developed a large left ovarian cyst, which led to a complete total abdominal hysterectomy and removal of the left ovary and fallopian tube. Pathology confirmed ovarian serous adenocarcinoma with microscopic focus of carcinoma in the left ovary. After numerous complications, the patient responded well to chemotherapy, CA-125 levels fell and no evidence of carcinoma was observed on subsequent imaging. To our knowledge, this is the first reported case of an ovarian serous adenocarcinoma in a patient with CAH. Although rare, we propose that the ovaries were the origin of androgen production and not residual adrenal tissue. The relationship between CAH and ovarian carcinomas has yet to be established, but further evaluation is needed given the poor survival rate of high-grade serous ovarian carcinoma.

Stimulation of protein and RNA synthesis by methylmercury chloride in the liver of intact and adrenalectomized rats

1981 ◽  
Vol 47 (2) ◽  
pp. 113-123 ◽  
Author(s):  
Saburo Omata ◽  
Hidemi Tsubaki ◽  
Kenji Sakimura ◽  
Mitsuru Sato ◽  
Ryuji Yoshimura ◽  
...  
Keyword(s):  
Rna Synthesis ◽  
Methylmercury Chloride ◽  
Protein And Rna Synthesis ◽  
Adrenalectomized Rats ◽  
Stimulation Of

Glucagon as a myocardial stimulant

1970 ◽  
Vol 8 (20) ◽  
pp. 77-79
Keyword(s):  
Pancreatic Islets ◽  
Heart Muscle ◽  
Physiological Effect ◽  
Inotropic Effect ◽  
Single Chain ◽  
Glucose Output ◽  
Stimulation Of

Glucagon is a polypeptide secreted by the α -cells of the pancreatic islets; it consists of 29 aminoacids arranged in a single chain. Its most important physiological effect is probably the stimulation of glucose output from the liver, but at concentrations higher than those found physiologically, glucagon increases the contractility of heart muscle as do the catecholamines. This inotropic effect of glucagon may therefore find a new role in therapeutics.

scholarly journals P0950EFFECT OF THYROID HORMONE TREATMENT ON RENAL REABSORPTION OF GLUCOSE IN ALLOXAN-INDUCED DIABETIC RATS

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Gireesh Dayma
Keyword(s):  
Blood Glucose ◽  
Thyroid Hormone ◽  
Glucose Homeostasis ◽  
Hepatic Glucose Production ◽  
Liver Perfusion ◽  
Glucose Production ◽  
Diabetic Rats ◽  
Hepatic Glucose ◽  
Glucose Output ◽  
Renal Expression

Abstract Background and Aims The thyroid hormone (TH) plays an important role in glucose metabolism. Recently, we showed that the TH improves glycemia control by decreasing cytokines expression in the adipose tissue and skeletal muscle of alloxan-induced diabetic rats, which were also shown to present primary hypothyroidism. In this context, this study aims to investigate whether the chronic treatment of diabetic rats with T3 could affect other tissues that are involved in the control of glucose homeostasis, as the liver and kidney. Method Adult male Wistar rats were divided into nondiabetic, diabetic, and diabetic treated with T3 (1.5 ?g/100 g BW for 4 weeks). Diabetes was induced by alloxan monohydrate (150 mg/kg, BW, i.p.). Animals showing fasting blood glucose levels greater than 250 mg/dL were selected for the study. Results After treatment, we measured the blood glucose, serum T3, T4, TSH, and insulin concentration, hepatic glucose production by liver perfusion, liver PEPCK, GAPDH, and pAKT expression, as well as urine glucose concentration and renal expression of SGLT2 and GLUT2. T3 reduced blood glucose, hepatic glucose production, liver PEPCK, GAPDH, and pAKT content and the renal expression of SGLT2 and increased glycosuria. Conclusion Results suggest that the decreased hepatic glucose output and increased glucose excretion induced by T3 treatment are important mechanisms that contribute to reduce serum concentration of glucose, accounting for the improvement of glucose homeostasis control in diabetic rats.

Respiratory responses to aortic and carotid chemoreceptor activation in the dog

1991 ◽  
Vol 70 (6) ◽  
pp. 2539-2550 ◽  
Author(s):  
F. A. Hopp ◽  
J. L. Seagard ◽  
J. Bajic ◽  
E. J. Zuperku
Keyword(s):  
Electrical Stimulation ◽  
Carotid Body ◽  
Carotid Sinus ◽  
Chemical Stimulation ◽  
Respiratory Drive ◽  
Carotid Sinus Nerve ◽  
Nerve Activity ◽  
Respiratory Reflexes ◽  
Respiratory Responses ◽  
Stimulation Of

Respiratory responses arising from both chemical stimulation of vascularly isolated aortic body (AB) and carotid body (CB) chemoreceptors and electrical stimulation of aortic nerve (AN) and carotid sinus nerve (CSN) afferents were compared in the anesthetized dog. Respiratory reflexes were measured as changes in inspiratory duration (TI), expiratory duration (TE), and peak averaged phrenic nerve activity (PPNG). Tonic AN and AB stimulations shortened TI and TE with no change in PPNG, while tonic CSN and CB stimulations shortened TE, increased PPNG, and transiently lengthened TI. Phasic AB and AN stimulations throughout inspiration shortened TI with no changes in PPNG or the following TE; however, similar phasic stimulations of the CB and CSN increased both TI and PPNG and decreased the following TE. Phasic AN stimulation during expiration decreased TE and the following TI with no change in PPNG. Similar stimulations of the CB and CSN decreased TE; however, the following TI and PPNG were increased. These findings differ from those found in the cat and suggest that aortic chemoreceptors affect mainly phase timing, while carotid chemoreceptors affect both timing and respiratory drive.

THE GROWTH OF THE VENTRAL AND DORSOLATERAL PROSTATE, THE COAGULATING GLANDS AND THE SEMINAL VESICLES IN FORCE-FED HYPOPHYSECTOMIZED CASTRATED ADRENALECTOMIZED RATS INJECTED WITH CORTISONE AND/OR INSULIN

1972 ◽  
Vol 71 (1) ◽  
pp. 179-190 ◽  
Author(s):  
Lars-Eric Tisell ◽  
Lennart Angervall
Keyword(s):  
Histological Examination ◽  
Anterior Pituitary ◽  
Adrenal Glands ◽  
Reproductive Organs ◽  
Seminal Vesicles ◽  
The Other ◽  
Protamine Zinc Insulin ◽  
Adrenalectomized Rats ◽  
Stimulation Of

ABSTRACT The growth of the ventral and dorsolateral prostate, the coagulating glands and the seminal vesicles was studied in force-fed hypophysectomized castrated adrenalectomized rats following daily injections for fourteen days of protamine zinc insulin or cortisone acetate alone or in combination. Cortisone was given in daily doses of 3 mg and insulin was administered in increasing daily doses of protamine zinc insulin up to 8 IU. Cortisone alone induced slight histological stimulation of the epithelium of the coagulating glands, while no stimulation was demonstrated in the other accessory reproductive organs. After insulin alone the weight of the accessory reproductive organs was slightly increased but no stimulation was demonstrated histologically. Cortisone and insulin given in combination induced distinct signs of stimulation of all the accessory reproductive organs as assesed by histological examination and weight determination of the organs. The results indicate that in the rat the growth stimulating effect of cortisone on the male accessory reproductive organs is markedly decreased or abolished in the absence of the anterior pituitary. Insulin can act synergistically with cortisone in promoting the growth of the accessory reproductive organs through effects which are not dependent on the presence of the adrenal glands or the anterior pituitary.

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