TY - JOUR
T1 - Localization, identification, and action of galanin in the frog adrenal gland
AU - Gasman, Stephane
AU - Vaudry, Hubert
AU - Cartier, Franck
AU - Tramu, Gerard
AU - Fournier, Alain
AU - Conlon, J. Michael
AU - Delarue, Catherine
PY - 1996
Y1 - 1996
N2 - The distribution of galanin-like immunoreactivity was studied in the adrenal gland of the frog Rana ridibunda using the indirect immunofluorescence technique. A dense network of varicose fibers immunoreactive to galanin was found in the adrenal tissue. A combination of HPLC analysis and RIA detection was used to characterize galanin-like immunoreactivity in frog adrenal gland extracts. The elution profile revealed the existence of a single form of galanin exhibiting the same retention time as synthetic frog galanin. The possible involvement of galanin in the regulation of corticosteroid secretion was investigated in vitro using a perifusion system for frog adrenal slices. For concentrations ranging from 10-9 to 3 x 10-6 M, synthetic frog galanin induced a dose-dependent inhibition of corticosterone and aldosterone release. Repeated pulses of galanin (10-6 M), given at 90-min intervals, resulted in a reproducible inhibition of corticosteroid secretion without any apparent tachyphylaxis. During prolonged administration of galanin (10-6 M), the steroidogenic effect of ACTH (10-9 M) was significantly reduced. In contrast, galanin did not attenuate the stimulation of corticosteroid secretion induced by the angiotensin II analog [Sar1,Val5]angiotensin II. These results show the occurrence of galanin in fibers innervating the frog adrenal gland. The data also demonstrate that synthetic galanin inhibits spontaneous and ACTH- induced corticosteroid release. Taken together, these findings suggest that galanin, released by nerve fibers in the adrenal tissue, can act locally as a modulator of steroid secretion.
AB - The distribution of galanin-like immunoreactivity was studied in the adrenal gland of the frog Rana ridibunda using the indirect immunofluorescence technique. A dense network of varicose fibers immunoreactive to galanin was found in the adrenal tissue. A combination of HPLC analysis and RIA detection was used to characterize galanin-like immunoreactivity in frog adrenal gland extracts. The elution profile revealed the existence of a single form of galanin exhibiting the same retention time as synthetic frog galanin. The possible involvement of galanin in the regulation of corticosteroid secretion was investigated in vitro using a perifusion system for frog adrenal slices. For concentrations ranging from 10-9 to 3 x 10-6 M, synthetic frog galanin induced a dose-dependent inhibition of corticosterone and aldosterone release. Repeated pulses of galanin (10-6 M), given at 90-min intervals, resulted in a reproducible inhibition of corticosteroid secretion without any apparent tachyphylaxis. During prolonged administration of galanin (10-6 M), the steroidogenic effect of ACTH (10-9 M) was significantly reduced. In contrast, galanin did not attenuate the stimulation of corticosteroid secretion induced by the angiotensin II analog [Sar1,Val5]angiotensin II. These results show the occurrence of galanin in fibers innervating the frog adrenal gland. The data also demonstrate that synthetic galanin inhibits spontaneous and ACTH- induced corticosteroid release. Taken together, these findings suggest that galanin, released by nerve fibers in the adrenal tissue, can act locally as a modulator of steroid secretion.
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U2 - 10.1210/endo.137.12.8940351
DO - 10.1210/endo.137.12.8940351
M3 - Article
C2 - 8940351
AN - SCOPUS:0030444929
SN - 0013-7227
VL - 137
SP - 5311
EP - 5318
JO - Endocrinology
JF - Endocrinology
IS - 12
ER -