This research proposal is designed to study several aspects of brain peptide functions by use of a variety of complementary experimental techniques. Experiments will focus on the role of somatostatin in pituitary regulation and on its postulated effects as a neurotransmitter in brain. Five separate but interrelated experimental approaches will be used: 1) The role of somatostatin, biogenic amine neurotransmitters and other brain peptides in episodic growth hormone(GH) secretion will be investigated in the unanesthetized, cannulated rat. 2) Factors that determine somatostatin release from brain tissue will be studied in vitro by use of a perifusion system developed in our laboratory. 3) The function of cerebrospinal fluid (CSF) as a potential system for distribution of peptides to brain tissues will be investigated by measurement of endogenous somatostatin secretion into CSF in the unanesthetized rabbit and by analysis of the fate of exogenously administered cold and radioactive-labeled somatostatin. Studies in the awake sheep will determine interrelationships between blood and CSF levels of GH, prolactin (PRL) and somatostatin. 4) The anatomic and physiologic significance of several peptides in the retina will be investigated. 5) The distribution and concentration of peptides in normal and abnormal human brain tissue will be determined. These experimental techniques will provide new information concerning the function of small-molecular weight peptides in brain function.

National Institute of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Research Project (R01)
Project #
Application #
Study Section
Biochemical Endocrinology Study Section (BCE)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Massachusetts General Hospital
United States
Zip Code
Maiter, D; Underwood, L E; Martin, J B et al. (1991) Neonatal treatment with monosodium glutamate: effects of prolonged growth hormone (GH)-releasing hormone deficiency on pulsatile GH secretion and growth in female rats. Endocrinology 128:1100-6
Hooi, S C; Koenig, J I; Gabriel, S M et al. (1990) Influence of thyroid hormone on the concentration of galanin in the rat brain and pituitary. Neuroendocrinology 51:351-6
Maiter, D M; Hooi, S C; Koenig, J I et al. (1990) Galanin is a physiological regulator of spontaneous pulsatile secretion of growth hormone in the male rat. Endocrinology 126:1216-22
Riskind, P N; Allen, J M; Gabriel, S M et al. (1989) Sex differences in vasoactive intestinal peptide (VIP) concentrations in the anterior pituitary and hypothalamus of rats. Neurosci Lett 105:215-20
Koenig, J I; Hooi, S; Gabriel, S M et al. (1989) Potential involvement of galanin in the regulation of fluid homeostasis in the rat. Regul Pept 24:81-6
Hooi, S C; Richardson, G S; McDonald, J K et al. (1989) Neuropeptide Y (NPY) and vasopressin (AVP) in the hypothalamo-neurohypophysial axis of salt-loaded or Brattleboro rats. Brain Res 486:214-20
Gabriel, S M; Milbury, C M; Nathanson, J A et al. (1988) Galanin stimulates rat pituitary growth hormone secretion in vitro. Life Sci 42:1981-6
Riskind, P N; Kolodny, J M; Larsen, P R (1987) The regional hypothalamic distribution of type II 5'-monodeiodinase in euthyroid and hypothyroid rats. Brain Res 420:194-8