Polina Lobacheva
Neuroendocrine control: the nervous system and the endocrine system work together to coordinate body functions and
control homeostasis: neuroendocrine system
Nervous systems release neurotransmitters that act on neurons, muscle fibers and glands (endocrine/exocrine). Nerve AP’s
produce their effects within milliseconds
Endocrine system releases hormones into extracellular fluids/bloodstream which delivers them to most body cells.
Hormones produce their effects within a few seconds to several hours
Hormones: Main hormone producing tissues: Hypothalamic hormone secreting neurons secrete
1. Organic chemical messengers / signalling released hormones (RH) or inhibitory hormones (IH) into blood vessels to regulate
molecules: amines, eicosanoids (ex. anterior pituitary hormone secretion
prostaglandins), steroids, proteins, peptides, 1. Hypothalamus: GHRH, CRH, TRH, GnRH, vasopressin (ADH), somatostatin, dopami
glycoproteins 2. Anterior pituitary gland: growth hormone, prolactin, ACTH, PSH, TSH, FSH, LH
2. Secreted by specialised glands, scattered cells 3. Posterior pituitary gland: Oxytocin, vasopressin (ADH)
and nerves 4. Thyroid glands: thyroid hormones (T3 and T4), calcitonin
3. Transported in the bloodstream or by simple 5. Parathyroid glands: parathyroid hormone
diffusion 6. Adrenal glands:
4. Categorised according to the target sites: a. Adrenal cortex: cortisol, aldosterone, adrenal androgens
endocrine, neurohormone, paracrine, b. Adrenal medulla: adrenaline, noradrenaline
neurotransmitter, autocrine, pheromone 7. Pancreas: insulin, glucagon
8. Ovaries (female): oestrogen, progesterone
9. Testes (male): testosterone
Hypothalamus and pituitary gland provide three important mechanisms of control:
1. Hypothalamus and anterior pituitary: secrete regulatory hormones (release and inhibitory), and these hormones
control the secretory activity of the anterior lobe of the pituitary gland
2. Hypothalamus and posterior pituitary: ADH and oxytocin are formed in the hypothalamus
3. Adrenal gland: sympathetic output to the adrenal medulla (adrenaline) and also ACTH control of cortisol release from
the adrenal cortex
, Polina Lobacheva
Stimuli for the secretion of hormones, many types of stimulation can cause hormone release: Hormone receptors and actions:
- Action potentials → hypothalamic neurohormones - Hormones can reach tissues / cells
- Hypothalamic neurohormones → anterior pituitary hormones by diffusion or via blood
- TSH from the anterior pituitary → thyroid hormones - Hormone actions can be either:
- Acetylcholine neurotransmitter → adrenal medulla hormones autocrine (on-self), paracrine (loca
- Glucose → insulin, glucagon endocrine (distant)
- Low / high blood Ca2+ → parathyroid / calcitonin hormones - Hormones exert targeted response
- Other ex. Tissue injury → histamine, cytokines because cells have specific recepto
Increased intracellular Ca2+ is required for the vesicles to fuse with the plasma membrane.
Water soluble (hydrophilic): cell surface receptors Lipid-soluble (hydrophobic): intracellular receptors
Neuroendocrine control: the nervous system and the endocrine system work together to coordinate body functions and
control homeostasis: neuroendocrine system
Nervous systems release neurotransmitters that act on neurons, muscle fibers and glands (endocrine/exocrine). Nerve AP’s
produce their effects within milliseconds
Endocrine system releases hormones into extracellular fluids/bloodstream which delivers them to most body cells.
Hormones produce their effects within a few seconds to several hours
Hormones: Main hormone producing tissues: Hypothalamic hormone secreting neurons secrete
1. Organic chemical messengers / signalling released hormones (RH) or inhibitory hormones (IH) into blood vessels to regulate
molecules: amines, eicosanoids (ex. anterior pituitary hormone secretion
prostaglandins), steroids, proteins, peptides, 1. Hypothalamus: GHRH, CRH, TRH, GnRH, vasopressin (ADH), somatostatin, dopami
glycoproteins 2. Anterior pituitary gland: growth hormone, prolactin, ACTH, PSH, TSH, FSH, LH
2. Secreted by specialised glands, scattered cells 3. Posterior pituitary gland: Oxytocin, vasopressin (ADH)
and nerves 4. Thyroid glands: thyroid hormones (T3 and T4), calcitonin
3. Transported in the bloodstream or by simple 5. Parathyroid glands: parathyroid hormone
diffusion 6. Adrenal glands:
4. Categorised according to the target sites: a. Adrenal cortex: cortisol, aldosterone, adrenal androgens
endocrine, neurohormone, paracrine, b. Adrenal medulla: adrenaline, noradrenaline
neurotransmitter, autocrine, pheromone 7. Pancreas: insulin, glucagon
8. Ovaries (female): oestrogen, progesterone
9. Testes (male): testosterone
Hypothalamus and pituitary gland provide three important mechanisms of control:
1. Hypothalamus and anterior pituitary: secrete regulatory hormones (release and inhibitory), and these hormones
control the secretory activity of the anterior lobe of the pituitary gland
2. Hypothalamus and posterior pituitary: ADH and oxytocin are formed in the hypothalamus
3. Adrenal gland: sympathetic output to the adrenal medulla (adrenaline) and also ACTH control of cortisol release from
the adrenal cortex
, Polina Lobacheva
Stimuli for the secretion of hormones, many types of stimulation can cause hormone release: Hormone receptors and actions:
- Action potentials → hypothalamic neurohormones - Hormones can reach tissues / cells
- Hypothalamic neurohormones → anterior pituitary hormones by diffusion or via blood
- TSH from the anterior pituitary → thyroid hormones - Hormone actions can be either:
- Acetylcholine neurotransmitter → adrenal medulla hormones autocrine (on-self), paracrine (loca
- Glucose → insulin, glucagon endocrine (distant)
- Low / high blood Ca2+ → parathyroid / calcitonin hormones - Hormones exert targeted response
- Other ex. Tissue injury → histamine, cytokines because cells have specific recepto
Increased intracellular Ca2+ is required for the vesicles to fuse with the plasma membrane.
Water soluble (hydrophilic): cell surface receptors Lipid-soluble (hydrophobic): intracellular receptors
