Hypothalamus & Pituitary Gland
GH enhances the uptake of ______ and protein _______
Amino acids and protein synthesis
IGF-I has _______ effects
Anabolic
IGF-I plays an important role in childhood growth and continues to have _____ effects in adults
Anabolic
The hypothalamus and pituitary gland have intimate _____ and ______ relationships
Anatomical and functional
The hypothalamic hormones can be delivered to the anterior pituitary _______ and in _____ concentration
Directly and in high concentration
At puberty, there is an enormous secretory ______, induced in females by _________ and males by ______
Burst Estrogen Testosterone
Hormones are secreted into the surrounding hypothalamic tissue and enter the nearby _____ plexus
Capillary
IGF-I is protective for _______ cells
Cartilage
The largest secretory burst occurs within 1 hour of falling _____
Falling asleep
Hypothalamic hormones are known as _____ hormones
Hypophysiotropic
Cell bodies that are located in the supraoptic and paraventricular nuclei of the hypothalamus are called _____ neurons
Magnocellular neurons
The neural portion of the pituitary is called the ______ and it represents a down-growth of the hypothalamus, located _____
Neurohypophysis Posterior
Antidiuretic hormone (ADH) and Oxytocin are ______
Neuropeptides
IGF-I has a _______factor that influences survival of neurons
Neurotrophic
Complementary regulation of GH and insulin secretion coordinates availability of ______ with anabolism and either caloric storage or mobilization
Nutrients
IGF-I stimulates _____ and _____ activity to increase bone growth
Osteoblasts and chondrocyte
IGF-has an anabolic factor for bone that activates _______
Osteocytes
A hormone that acts as an intermediate in the stimulation of tissue growth by GH
Somatomedin
Both growth hormone and IGF-I stimulate the secretion of _________ by the hypothalamus
Somatostatin
Growth hormone
Somatotrophs
During childhood, growth hormone secretion remains relatively _____
Stable
GH releasing hormone _______ GH production
Stimulates
Neural structure
Neurohypophysis
The regulation of growth hormone secretion includes ___ negative feedback loops
3 negative feedback loops
Epithelial component
Adenohypophysis
Only the cell of the _____ pituitary receive high concentrations of the hypothalamic hormones
Anterior
GH regulates blood glucose- exerts ________ activity by suppressing insulin's ability to promote glucose uptake in the peripheral tissues
Anti-insulin
The hypothalamus and pituitary gland function in a _________ fashion to orchestrate many of the endocrine systems
Coordinated
Adrenocorticotropic hormone
Corticotrophs
After puberty, the rate of growth hormone secretion ______ to a stable level
Declines
REM sleep ______ the secretion of growth hormone
Decreases
Th pituitary gland is composed of an ______ component and a ______ structure
Epithelial component Neural structure
Major regulatory factors for GH secretion include
GH releasing hormone (GHRH) Somatostatin (SRIF) GH releasing peptide (ghrerin) Insulin-like growth factor (IGF-I)
Ghrelin is the hormone linking ______ axis
Gastrointestinal-pituitary
GH increases ______ in the liver
Gluconeogenesis
Follicle-stimulating hormone
Gonadotrophs
Luteinizing hormone
Gonadotrophs
Together GH and IGF promote _____ and influence regulation of _____
Growth Metabolism
In contrast to the other pituitary hormones, which stimulate specific target glands, ______ hormone has multiple effects throughout the body
Growth hormone
Anterior pituitary hormones include
Growth hormone (GH) Prolactin (PRL) Follicle-stimulating hormone (FSH) Luteinizing hormone (LH) Adrenocorticotropic hormone (ACTH) Thyroid-stimulating hormone (TSH)
Pituitary hormones and the hypothalamus also controls ______, ___ production, ______, and ________
Growth, milk production, ejections and osmoregulation
IGF-I is anabolic because it causes skeletal muscle _____
Hypertrophy
The blood from these capillaries (venous blood) drains into the ________ portal vessels and is derived directly to the anterior lobe of the pituitary
Hypophyseal
Hypothalamic releasing hormones and releasing inhibiting hormones are synthesized in _______ neurons
Hypothalamic neurons
Hypothalamus and anterior pituitary are linked directly by the ____________ portal blood vessels
Hypothalamic-hypophyseal portal blood vessels
On stimulating of these hypothalamic neuroendocrine cells, RH/RIH (release/release inhibiting hormones) are released into the capillary plexus flow through the ________ portal vessels
Hypothalamic-hypophysial portal vessels
All endocrine functions of the pituitary gland are regulated by the _______ and by negative and positive-feedback loops
Hypothalamus
Ghrelin is synthesized in the ______
Hypothalamus
The posterior pituitary is a collection of nerve axons whose cell bodies are located in the _____
Hypothalamus
Somatotropin releasing-inhibiting hormone is secreted by the ________ and acts on the somatotrophs to ________ GH secretion
Hypothalamus Inhibit
Growth hormone plays an important role in metabolism of ______, ______, and ______
Lipids, proteins, and carbohydrates
IGF-I is produced primarily in the ____
Liver
Finally, growth hormone secretory rates and pulatility decline to their _____ levels
Lowest
GH acts directly and indirectly through _______
IGF-I
Largest secretory burst specifically in which stages of sleep
III and IV
Growth hormones is the single most ______ hormone for normal growth to adult stature
Important
Ghrelin binds to an active receptor in the hypothalamus to ______ GH release and food intake
Increase
The rate of growth hormone secretion ______ steadily from birth into early childhood
Increased
Most growth occurs through the _____ method
Indirect
ADH and oxytocin are released from secretion into the capillary plexus of the _________ artery
Inferior hypophysial artery
IGF-I ______ secretion of GH by the anterior pituitary
Inhibit
GHRH _____ its own secretion from the hypothalamus via an ultrashort-loop feedback
Inhibits
Somatostatin _______ GH production
Inhibits
IGF-I is similar in molecular structure to _____
Insulin
At high concentration, IGF is capable of activating the _____ receptor, it can also complement for the effects of ______
Insulin receptor Insulin
GH stimulates production of ________ (IGF-I)
Insulin-like growth factor
Prolactin (PRL)
Lactotrophs
Growth hormone is secreted throughout ____
Life
IGF-I also plays a major role in muscle growth, promoting the differentiation and proliferation of a type of progenitor cell called ________ that gives rise to muscle cells
Myoblast
The resultant changes in target gland hormones and metabolic substrates exert _______ feedback control
Negative
The hypothalamus receives _____ input from many areas of the brain, this information, related to the well-being of the body, is integrated in the hypothalamus
Neural
Physiological regulation mechanisms for GF secretion include
Neural endogenous rhythm Sleep Stress Exercise Nutritional and metabolic signals
IGF-I is also produced in target tissues in _____/_____ fashion
Paracrine/autocrine fashion
Ghrelin is a _______ produced mainly by the ______
Peptide Stomach
Each of the anterior pituitary hormones is a _____ or _____
Peptide or polypeptide
Functionally, the hypothalamus controls the _______gland by both neural and hormonal mechanisms
Pituitary gland
IGF-I is _______ hormone produced mainly by the _____ in response to the GH stimulus
Polypeptide hormone Liver
Inferior hypophysial artery is the primary blood supply to the _______
Posterior pituitary
IGF-I (somatomedin C) increases growth promoting activities in many tissues and cartilage with a ________ duration of action
Prolonged duration of action (20 hours)
The effects throughout the body include (5)
Promotion of linear growth Promotion of protein deposition in tissues Promotion of fat utilization for energy Impairment of carbohydrate utilization for energy Growth hormone has profound effects on protein, carbohydrate, and fat metabolism
Growth hormone is secreted the highest during _____ and decreases in _____ life
Puberty Adult
Growth hormone is secreted in ______ pattern (secretion occurring approx. every 2 hours)
Pulsatile
Somatostatin and GHRH are secreted in alternation, giving rise to the markedly _______ secretin of GH
Pulsatile
During _____ sleep, brain mimics activity during the waking state. The eyes remain closed but move rapidly from side to side, perhaps related to the intense dream and brain activity that occurs during this stage
REM
Hypothalamic hormones include_____ and _____ hormones, and also control secretion of the anterior pituitary hormones
Releasing and inhibiting hormones
The cell bodies of the neurons that project to post pituitary are located either in the _____ or the _____ of the hypothalamus
Supraoptic nuclei Paraventricular nuclei
The hypothalamic hormones do not appear in the ______ circulation in high concentrations
Systemic
Pituitary hormones and the hypothalamic regulates which organs
Thyroid Adrenal Mammary glands Gonads
Thyroid-stimulating hormone
Thyrotrophs
Hypophysiotropic hormones include (6)
Thyrotropin-releasing hormone (TRH) Gonadotropin-releasing hormone (GnRH) Corticotropin-releasing hormone (CRH) Growth hormone-releasing hormone (GHRH) Growth hormone- inhibiting hormone (somatostatin) Prolactin-inhibiting hormone (PIH)
GH promotes the use of lipids by promoting the breakdown of _____ and _______ in cells
Triglycerides and oxidation in cells
GH acts as a ______ hormone acting on the ____ to produce IGF-I
Tropic hormone Liver