Simultaneous release of neurotensin, somatostatin, enkephalins and catecholamines from perfused cat adrenal glands.

Acid extracts of cat adrenal medullae were found to contain neurotensin-like (0.71 +/- 0.21nmol/gm), met-enkephalin-like (11.71 +/- 2.87nmol/gm), leu-enkephalin-like (1.95 +/- 0.11nmol/gm) and somatostatin-like (1.57 +/- 0.63pmol/gm) immunoreactivities. Using isolated retrogradely perfused cat adrenal glands the secretory responses to acetylcholine (ACh), nicotine and potassium ions (K+) were studied. Spontaneous secretion of catecholamines, neurotensin-like, met-enkephalin-like, leu-enkephalin-like and somatostatin-like immunoreactivities was negligible. However, ACh (5.5 X 10(-5)M), nicotine (2.2 X 10(-5)M) and 55mM K+ all evoked the simultaneous release of noradrenaline, adrenaline and the four neuropeptide immunoreactivities. The ACh stimulated secretion of the four neuropeptides could be prevented by perfusion with hexamethonium (C6, 2.8 X 10(-4)M). The concomitant release of these neuropeptides with catecholamines suggests that they may have a role in the modulation of stress responses.