ROLE OF THE NEUROHYPOPHYSIAL HORMONE IN THE SECRETION OF ANTERIOR PITUITARY HORMONE.
Abstract
Acid phosphatase activity was determined in the rat pituitary, median eminence and anterior hypothalamus. Dehydration caused a significant increase, while Pitressin a decrease in the enzyme activity of the posterior pituitary. The activity of adenohypophysial acid phosphatase was elevated after prolonged exposure to cold. Chronic exposure to heat did not affect the enzyme activity in all tissues studied. Thyroidectomy caused a significant elevation of the enzyme activity, while thyroxine, given in vivo, effectively suppressed. These results suggest a possible relation of adenohypophysial acid phosphatase to thyrotropin secretion. Intracellular distribution of acid phosphatase was determined by the use of differential centrifugation. It was found that the enzyme in the soluble fraction was more inhibited by formaldehyde and less by tartrate or fluoride as compared with that in the mitochondrial and microsomal fractions. Acid phosphatase of rat adenohypophysis was chromatographically separated into three and that of the anterior hypothalamus into two major components of activity. Prolonged exposure of animals to cold brought about an increase in per cent distribution of the first major component. From the similarity in the pattern of per cent inhibitions by various inhibitors between these chromatographic components and the fractions after differential centrifugation, the possibility was suggested that the acid phosphatase primarily related to the secretory activity may be separable as an independent peak in Deae-Sephadex column fractions. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 14, 1965
- Accession Number
- AD0474958
Entities
People
- Shinji Itoh
Organizations
- Hokkaido University