anterior pituitary


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Related to anterior pituitary: thyroid gland, pituitary gland, adrenal gland

anterior pituitary

anterior pituitary

1. Adenohypophysis.
2. A preparation of dried, defatted, powdered anterior lobe of the pituitary gland of domestic animals.
See also: pituitary
Anterior talofibular ligament. Right ankle, lateral view.

anterior pituitary

endocrine gland, part of the pituitary gland at the base of the brain. Secretes growth hormone (with widespread actions on growth and metabolism), prolactin (promoting lactation) and 'trophic' hormones that regulate in turn the endocrine secretions of the adrenal cortex, of the thyroid gland, and those from the gonads involved in reproductive function. All these secretory functions are themselves controlled by 'releasing' and in some instances also 'inhibitory' hormones from the hypothalamus via local blood vessels. See also hormones, posterior pituitary; Table 1.
Table 1: Hormones
Site of productionName of hormoneMain targetsInvolved in regulating:Secretion controlled by:
HypothalamusReleasing and inhibiting hormonesAnterior pituitary (via local blood vessels)Secretion of anterior pituitary hormonesOther brain regions; feedback re regulated hormones and their actions
Neurohormones released from posterior pituitary:
OxytocinUterus, breastsLabour and lactationAfferent information from target organs
Antidiuretic hormone (ADH, vasopressin)KidneysWater loss: ECF volume and osmolalityHypothalamic osmoreceptors
Anterior pituitary(Human) growth hormone (H)GHMost cellsGrowth and metabolismHypothalamic releasing and inhibiting hormones via local blood vessels
ProlactinBreastsMilk production
Trophic hormones:
Thyroid-stimulating (TSH)Thyroid glandThyroid secretions
GonadotrophinsOvary or testisGerm cell maturation and hormone secretions
Adrenocorticotrophic (ACTH)Adrenal cortexCortisol secretion
Pineal bodyMelatoninWidespread, including brain, thymus, etc.
  • Sleep/wake cycle
  • Antioxidant
  • Immune system
Hypothalamus; varying light input from retina
Thyroid
  • Thyroxine
  • Triiodothyronine
  • Calcitonin
  • Most cells
  • Bone, kidneys, gut
  • Cellular oxidative metabolism
  • Decreases ECF [Ca2+]
  • TSH from anterior pituitary. Negative feedback from blood hormone concentration
  • ECF [Ca2+]
ParathyroidsParathormoneBone, kidneys, gut
  • Calcium and phosphorus absorption, secretion and turnover in bone.
  • Increases ECF [Ca2+]
ECF [Ca2+]
Adrenal: Cortex
  • Cortisol
  • Aldosterone
  • Androgens
  • Most cells
  • Kidneys
  • Gonads & other tissues
  • Metabolism
  • Response to stress
  • Na and K balance
  • Sex characteristics and reproductive function
  • ACTH from anterior pituitary
  • ECF [Na+] [K+]
  • Renin-angiotensin
  • ACTH
Medulla
  • Adrenaline
  • Noradrenaline
Heart, smooth muscle, glandsCardiovascular and metabolic adjustments to activity and stressSympathetic nervous system
Atrial wallAtrial natriuretic hormoneKidneysBlood volume; increases sodium (therefore also water) loss in urineStretch of atrial wall by venous pressure
Gonads: TestisAndrogens (mainly testosterone)Genitalia and other tissuesReproductive function and sex characteristicsAnterior pituitary gonadotrophins
Ovary
  • Oestrogens
  • Progesterone
Uterus, breasts and other tissuesMenstrual cycle, pregnancy, lactation
Pancreas
  • Insulin, glucagon
  • Somatostatin
  • Most cells
  • Other secretory cells in the pancreas
Blood levels, storage and cellular uptake of nutrients, notably glucose, but also proteins and fatsBlood levels of nutrients; autonomic nervous system; other gastrointesinal hormones
Alimentary tract
StomachGastrinGastric acid-secreting cellsGastrointestinal functions: motility, digestive juices and other secretionsLocal chemical and mechanical factors in the alimentary tract
Small intestine
  • Secretin
  • Cholecystokinin- pancreozymin (CCK-PZ)
  • Somatostatin, motilin
  • Other peptide hormones including vasoactive intestinal peptide (VIP)
  • Widespread on
  • GI tract
Several GI functions including bile flow, pancreatic enzyme and exocrine secretionsIngestion of food, distension of GI tract

anterior

situated at or directed toward the front; opposite of posterior. In quadrupeds the use of the term is limited to parts of the head but is often used to mean cranially. In bipeds such as humans it is synonymous with ventral.

anterior abdomen pain
elicited pain in the anterior abdomen caused, in cattle, by reticulitis, hepatic or splenic abscess, abomasal ulcer and intestinal obstruction.
anterior chamber
the part of the eyeball between the cornea and the iris, filled with aqueous humor.
anterior chamber angle
see iridocorneal angle.
anterior compartment
chamber of the eye bounded by the iris and cornea; contains the aqueous humor as it moves to the filtration angle; called also anterior chamber.
anterior cruciate ligament
see cranial (anterior) cruciate ligament.
anterior (cranial) drawer sign
cranial, nonrotary movement of the proximal tibia in relation to the distal femur. Normally restricted by the cranial (anterior) cruciate ligament and used as a diagnostic test for rupture of that structure.
anterior epithelial layer
of the cornea is a noncornified, stratified, squamous epithelium, continuous with the bulbar conjunctival epithelium.
anterior functional stenosis
achalasia of the reticulo-omasal sphincter causing ingesta to accumulate in the reticulorumen.
anterior limiting membrane
of the cornea is a combination of the basement membrane, a felted layer of fine collagen fibers; substantial only in primates.
anterior pituitary
anterior pituitary hormones
anterior station trypanosomes
a section of the genus Trypanosoma in which the infectious stages accumulate in the mouthparts and salivary glands of the intermediate host so that the parasite is transmitted when the insect vector takes a blood meal. Called also Salivaria. See also posterior station trypanosomes.
anterior vena cava
see vena cava.
References in periodicals archive ?
Short-chain fatty acids inhibit the release and content of growth hormone in anterior pituitary cells of the goat.
When circulating levels of thyroid hormones are low, the hypothalamus responds by releasing TRH, which then stimulates thyrotropic cells in the anterior pituitary to produce and secrete TSH.
To evaluate the proposed algorithm for accuracy and efficiency, these stepwise diagnoses were compared with the reference diagnosis and total stains used in the final algorithm were compared with the number used in our prior algorithm, which included IHC for all 6 anterior pituitary hormones plus CAM5.
Administration of stress doses of glucocorticoids protects against possible impairment of ACTH secretion because of manipulating and exploration of the anterior pituitary, the stalk, or the hypothalamus.
Sixth study shows that in the absence of pituitary stalk visibility, anterior pituitary function failure may also present.
Pit-1 gene has been identified as the pituitary specific transcription factor that regulates the expression of the growth hormone (GH) and prolactin (PRL) genes in the anterior pituitary.
This growth process is stimulated by somatotrophin (growth hormone) released by the anterior pituitary gland.
This may be due to lower level of estradiol 17B secretion from the preovulatory follicle or higher thresh hold of anterior pituitary to estradiol 17B for the adequate and timely release of L.
By preventing LH-RH from binding with the LH-RH receptor in the anterior pituitary gland and suppressing the secretion of luteinising hormone (LH) and follicle stimulation hormone (FSH) from the anterior pituitary gland, TAK-385 controls the effect of LH and FSH on the ovary, reduces the level of estrogen in blood.
Bovine growth hormone (bGH) or Somatotropin, a peptide hormone of anterior pituitary gland, increases rate of protein synthesis and mobilization of fatty acids; and decreases the rate of glucose utilization (Bauman, 1992).
Human prolactin (PRL) is a hormone secreted by the anterior pituitary lactotropic cells.

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