Enzymatic Degradation of Hypothalamic Hormones at the Pituitary-Cell Level: Possible Involvement in Regulation Mechanisms
Within the concert of regulatory mechanisms balancing the functions of an organism according to the needs of the body, there are principally two control levels. On one hand, the biological effect exerted by a given concentration of an active substance is dependent on the various physiological parameters that collectively determine the “responsiveness” of the target. On the other hand, the mechanisms regulating the hormone concentrations at physiologically appropriate levels are evidently of fundamental importance, since under given physiological conditions the physiological response is, within certain limits, directly correlated with the concentration of the biologically active substance that becomes effective at the target site. Among these mechanisms, the controlled inactivation of a biologically active substance is an eminently important event. This becomes evident in the case of certain pathological disorders in which loss of control over destruction might be the primary cause of certain endocrine diseases (Knight et al., 1973).
KeywordsSecretory Granule Pyroglutamic Acid Amino Acid Amide Hypothalamic Hormone Hypophyseal Hormone
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