Mechanisms Flashcards
By ions via gap junctions
Direct
What are the Mechanisms of Intercellular Communication?
- Direct
- Paracrine
- Endocrine
- Synaptic
By Paracrine factors via the extra cellular fluid
Paracrine
By hormones via the blood circulatory system
Endocrine
By neurotransmitters across neural junctions
Synaptic
What are the Endocrine Glands
Hypothalamus Pituitary Gland Pineal Gland Thyroid Gland Parathyroid Gland Adrenal Gland Pancreas
what are the Endocrine Tissues in Organs
Intestines Kidneys Liver Heart Thymus Gonads Placenta Adipose Tissue
A very defined structure of Tissues are
Endocrine Glands
A group of cells that are found within organs
Endocrine Tissues in Organs
Hormones are ___ ____ of various body functions such as _____ and _____. They are ___ into and transported by the blood to affect the ____ of their ____. Hormones are ____ for certain ____ cells because hormones bind to _______ on their target ___.
Chemical regulators; growth; reproduction
Secreted;functions; target cells
Specific; target cell; specific receptors; cell
Compounds acting as hormones are classified according to their \_\_\_\_\_\_ as: 1) 2) 3) 4) 5)
Chemical structure; Steroids Monoamines Oligopeptides Glycoproteins Polypeptides
Made from lipids or cholesterol
Steroids
Vitamin D is a
Steroid
Made from a single amino acid which is modified or repeated
Monoamines
A thyroid hormone is
Monoamines
Made from 3 - 10 amino acids
Oligopeptides
Oxytocin is what
Oligopeptides
Made from carbohydrates - proteins complexes
Glycoproteins
Luteinizing hormone
Glycoproteins
Made from 14-199 amino acids
Polypeptide
Insulin and glucagon
Polypeptide
What is a hormone receptor
they are protein molecules located on the cell membrane, cytoplasm, or nucleus
Steroid hormones bind to ____ associated with _____.
Nuclear receptors ; DNA transcription
Thyroid hormones bind to _____ on ____ or ____.
Cytoplasmic receptors; mitochondria; ribosome
What hormones bind to cell membrane receptors and activate second messenger systems?
All other hormones
Hydrophilic
Has a strong attraction to water not fat
Hydrophobic
Having little to no attraction to water
When blood level of the endocrine gland hormone reach an optimum value, it inhibits secretion of the hypothalamic and anterior pituitary hormones that stimulate the endocrine gland.
Negative Feed back control of secretion
When action of an endocrine gland hormone reach an optimum level, it increases the secretion of the hormone that stimulated the action.
Positive Feed Back control of Secretion
What is a central area of the basal brain limbic system
The Hypothalamus
The Hypothalamus consist of a large number of ____ that modify and control the body functions VIA _____.
Nuclei; The Hypothalamic Hormones
What are the hypothalamic hormones
1) GHRH
2) GHIH
3) PRH
4) PIH
5) CRH
6) TRH
7) GnRH
8) OT
GHRH
Growth Hormone Releasing Hormone
GHIH
Growth Hormone Inhibiting Hormone (somatostatin)
PRH
Prolactin Releasing Hormone
PIH
Prolactin Inhibiting Hormone (Dopamine)
CRH
Corticotropin releasing hormone
TRH
Thyrotropin releasing hormone
GnRH
Gonadotropin releasing hormone
ADH
Anti diuretic hormone
OT
Oxytocin
Pituitary Gland
A small gland that is connected to the hypothalamus by the infundibulum
What are the two parts of the pituitary gland
Anterior pituitary (adenohypophysis) Posterior Pituitary (neurohypophysis)
____ derived from the neural brain tissue and connects to hypothalamus by the hypothalamic hypophyseal tract axons
Posterior Pituitary
____ derived from ectodermal tissue in the roof of the embryonic mouth and connects to the hypothalamus by the hypothalamic hypophyseal portal system
Anterior Pituitary
Oxytocin OT
Made in the hypothalamus then stored and secreted from the posterior pituitary
Oxytocin target tissues are the ____ of the reproductive systems in both male and females
Smooth muscle
What does oxytocin stimulate
- semen propelling during ejaculation
- uterine contractions during labor
- milk ejection during nursing
Antidiuretic Hormone (ADH) (Vasopressin)
Made in the hypothalamus them stored and secreted from the posterior pituitary
ADH target tissues are ___ and ____
Kidneys and blood vessels
What does ADH do
- increases water reabsorption in the kidneys to increase blood volume
- causes vasoconstriction of blood vessels to increase blood pressure
Human Growth Hormone (hGH) secretion is controlled by hypothalamic ____ and ____
GHRH
GHIH
hGH targets all cells especially where?
Skeletal and muscle tissues
What does hGH stimulate
1) directly stimulates stem cells growth and differentiation
2) stimulates liver synthesis and release of somatomedins
____ mediated growth hormone functions by stimulating stem cells growth and differentiation
Somatomedins
What is the result of somatomedins
Results in growth to adulthood and maintenance of skeleton and muscles during adulthood.
