Endocrine Lec Flashcards
4 classes of chemical messengers
Autocrine - eicosanoid
Paracrine - histamine
Neurotransmitter - Acetylcholine, epinephrine
Endocrine - thyroid hormones, growth hormones, insulin, epinephrine, estrogen, progesterone, testosterone, PG
organic substances,
produced in small amounts by specific tissues (endocrine glands), secreted into the blood stream to control the
metabolic and biological activities in the target cells.
SYSTEMIC TARGET HORMONE INCLUDES
EXAMPLE, KIDNEY, TESTES OVARY ETC
NEUROHORMONES
• Thyrotrophin- releasing hormone (TRH)
• Corticotrophin-releasing hormone (CH)
• Gonadotropin-releasing hormone (GnRH)
Growth hormone-releasing hormone (GHRH)
• Growth hormone-inhibiting hormone
• Prolactin-inhibiting hormone
• Oxytocin
• Vasopressin
2 refelex in lactation (oxytocin)
Letdown reflex
Milk ejection reflex
The pituitary gland lies in the ___________ of the __________ below the ________.
Hypophyseal fossa (Sella turcica)
Sphenoid bone
hypothalamus
Division of pituitary gland
Anterior pituitary gland (Adeno hypophysis)
Posterior pituitary gland (neurohypophysis)
Hormones produced by anterior pituitary gland
•Growth hormone (GH)
• Thyroid-stimulating hormone (TSH)
• Adrenocorticotrophic hormone (ACTH)
• Prolactin (PRL)
• Gonadotrophins
1. Luteinizing hormone (LH)
II. Follicle-stimulating hormone (FSH)
The growth hormone’s release are;
Stimulated by:
Suppressed by:
Secreted by:
Growth releasing hormone (GHRH)
Growth hormone releasing inhibiting hormone (GHRIH)
Hypothalamus
After birth suckling simulate the:
Prolactin secretion and lactation
In females LH and FSH stimulate the secretion of
Oestrogen
Progesterone
In males LH stimulates the ____ ____ to produce _____
Interstitial cells
Testosterone
(Posterior pituitary gland)
Axon terminal release these two hormone within the posterior pituitary gland.
- Oxytoxin
- Antidiuntic hormone (ADH, Vasopressin)
Adh or the antidiuretic hormone acts on the:
convoluted tubules and collecing ducts of thenephrons of lichegs.
2 receptors of adh
Osmoreceptors *detect increased osmotic pressure
Baroreceptors * (aortic arch, carotid sinus) detect decreased blood pressure
Thyroid gland function: secretion of;
thyroxine and triiodothyronine
calcitonin
Thyroid gland hormones
Thyroxine (T4)
Triiodothyronine (T3)
produce thyroid hormone
Thyroid follicles
produce calcitonin
C-cells
2 lobes in the thyroid gland is connected by the
isthmus
4 parathyroid glands in humans
•2 superior and 2 inferior on posteromedial aspect of thyroid lobes
Cells in parathyroid galnd
Chief cells
Oxyphill cells
Red blood cells
Target organs for parathyroid gland (PTH) are:
bone, kidney and intestine
Major function of parathyroid glands
Maintain body’s calcium and phosphate level
Parathyroid glands mobilizes _____ and ____ from the bones.
Calcium and phosphate
2 layers of adrenal glands
Cortex
Medulla
Three zones of adrenal cortex
- zonaglomerulosa- is narrow and the cells are in a whorled pattern.
- zonafasciculata- wide and the cells lie in columns and
- zonareticularis- more randomly organised.
(MEDULLA)
Catecholamines
Adrenaline
Noradrenaline
Dopamine
Enkephalin
2 classes of steroids hormones
Sex steroids
Corticosteroids
2 classes of corticosteroids
Glucocorticoids
Mineralocorticoids
adrenocortical hormones
Mineralocorticoids
Glucocorticoids
Adrenal androgens
Adrenal gland hormone and target tissue
Adrenaline, sympathetic effectors
Noradrenaline, sympathetic effectors
Corticosteroids, all body tissue
Androgens, sex organs
Mineralocorticoids, kidney
The pancreas is composed of two major types of tissues.
Acini
Islets of langerhans
4 types of cells of islets of langerhans
Alpha cells
Beta cells
Delta cells
PP-cells
2 amino acid chains of insulin
Alpha chain
Beta chain
Non-living substances; accessories of the reproductive system
Fluids
Hormones
Pheromones
2 kinds of glandular structures in ovary
Graafian follicles
Corpus luteum
Hormones of Ovaries
Estrogen
Progesterone
Relaxin
Estrogen are of three types.
B-Estradiol
Estrone
Estriol
Major endocrine system
Hypothalamus
Pituitary gland
Thyroid and parathyroid
Thymus
Pancreas
Adrenal gland
Ovary
Testes
