Neurosecretion Neurosecretion • Secretory neuron on a blood vessel • Change internal/external signals into chemical signals • Found in all animals • In vertebrates, the posterior pituitary connects to the hypothalamus by neurosecretion • Axonoplasmic flow/neurophysin Neurosecretion Neurosecretion Regulation of Endocrine Secretions • Few endocrine glands are controlled by the nervous system – Pineal Gland – Adrenal medulla – Kidney • All other regulation is chemical Negative feedback Positive feedback Negative Feedback Positive Feedback General Mechanisms of Regulation of Hormone Secretion Regulation of Secretion Multiple Control Systems • Aid in accomplishing multiple functions • Create different levels of complexity in control • Regulate the amount of time of action • Examples: – Parathyroid hormone – Thyroid hormone Multiple Control Systems• Localization of action – Receptors • Receptor hypothesis • Diversity of function – Second messenger systems Main Vertebrate Endocrine glands and functions Main Vertebrate Endocrine glands and functions Main Vertebrate Endocrine glands and