Faculty Collaboration Database

ACTH and vasopressin responses to insulin-induced hypoglycemia in intact and neurohypophysectomized conscious dogs. Neuroendocrinology 1991 Jan;53(1):85-90

Date

01/11/1991

Pubmed ID

1646414

DOI

10.1159/000125702

Scopus ID

2-s2.0-0026089346 (requires institutional sign-in at Scopus site)   16 Citations

Abstract

Factors from the neurohypophysis are important in the control of anterior pituitary function. This study evaluated the hypothesis that the neurophypophysis is an integral component of the adrenocorticotropin (ACTH) response to certain stimuli. Furthermore, we investigated the possibility that the importance of the neurohypophysis during corticotropic stimuli can be classified by the magnitude of the systemic vasopressin response induced. The ACTH response to insulin-induced hypoglycemia (INS), nitroprusside hypotension (NP), or ovine corticotropin-releasing factor (CRF) infusion (20 ng/kg/min) was measured in dogs before (intact) and greater than 2 weeks after selective transbuccal neurohypophysectomy (NHX). INS (0.2 U/kg) resulted in a significant decrease in plasma glucose from 93 +/- 1 to 33 +/- 2 mg/dl at 30 min and a significant increase in plasma ACTH from 53 +/- 10 to 306 +/- 33 pg/ml in intact dogs whereas the vasopressin (AVP) response was small (2.8 +/- 0.3 to 5.5 +/- 0.7 pg/ml). NHX had no effect on the blood glucose or ACTH response to INS. NP resulted in large increases in ACTH from 54 +/- 8 to 351 +/- 89 pg/ml and in AVP from 2.7 +/- 0.2 to 272 +/- 98 pg/ml. In contrast to INS, NHX significantly attenuated the ACTH and AVP responses to NP. The ACTH response to CRF was not attenuated by NHX, indicating normal pituitary corticotropic function. In summary, NHX attenuated the ACTH response to hypotension (large peripheral AVP response) but not to INS or CRF (small peripheral AVP response).(ABSTRACT TRUNCATED AT 250 WORDS)

Author List

Raff H, Papanek PE, Cowley AW Jr

Authors

Allen W. Cowley Jr PhD Professor in the Physiology department at Medical College of Wisconsin
Paula Papanek PhD, MPT, LAT, FACSM Associate Professor & Director of Exercise Science in the Exercise Science & Physical Therapy department at Marquette University
Hershel Raff PhD Professor in the Academic Affairs department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adrenocorticotropic Hormone
Animals
Blood
Blood Glucose
Corticotropin-Releasing Hormone
Dogs
Hydrocortisone
Hypoglycemia
Hypophysectomy
Hypotension
Insulin
Male
Nitroprusside
Osmolar Concentration
Potassium
Sodium
Vasopressins