ADRENOMEDULLARY HORMONAL AND GLYCEMIC MODULATION FOLLOWING GONADOTROPIN AND SEX HORMONE ADMINISTRATION IN THE SOFT-SHELLED TURTLE LISSEMYS PUNCTATA PUNCTATA

Abstract

The aim of the current investigation was to ascertain whether gonadotropins and sex hormones can modulate adrenomedullary and glycemic functions in turtles. Exogenous FSH (3.0 µg/100 gm body wt daily for 10 days) stimulated adrenomedullary activity by increasing nuclear diameter and cytoplasmic degranulation, and elevating adrenal norepinephrine and epinephrine, and blood glycemic levels in turtles. LH (3.0 µg/100 gm body wt daily for 10 days) had no significant effect and the combined treatment of FSH and LH (3.0 µg each/100 gm body wt daily for 10 days) failed to show further adrenomedullary stimulation and hyperglycemia beyond that of FSH alone. Estrogen treatment in low dose (25 µg/100 gm body wt daily for 10 days) had no significant effect on adrenomedullary activity or glycemia, but at higher doses (50 µg or 100 µg/100 gm body wt daily for 10 days) showed dose-dependent adrenomedullary stimulation by inducing the same manifestations as those of FSH. Progesterone in low dose (25 µg/100 gm body wt daily for 10 days) had no perceptible effect, but in other doses (50 µg/100 µg per 100 gm body wt daily for 10 days), suppressed dose-dependent adrenomedullary activity by reversing the changes to those of estrogen. Simultaneous treatment with estrogen and progesterone (50 µg each/100 gm body wt daily for 10 days) failed to show further changes beyond that of estrogen alone.

ACKNOWLEDGMENTS

This work was supported by a Special Assistance grant (No. UGC/496/SPA/Zoo/81) from the University Grants Commission, Government of India, New Delhi, to the Department of Zoology, University of Calcutta, with a Junior and a Senior Research Fellowships awarded to the first author (PPR) and by a minor research grant (No. F/PSW-045/99/00/ERO) from UGC awarded to PPR.