The Endocrine System: Hypothalamus & Pituitary Gland Control, Endocrine Pathologies-Lecture 7 Exam 2 Flashcards
The two hormones secreted by the posterior pituitary and the hormones’ primary
targets and effects
Oxytocin & ADH/Vasopressin
The Hypothalamus’s Role in Releasing Posterior Pituitary Hormones
Makes Oxytocin & ADH and then sends nerve signals throughout the pituitary stalk
Growth Hormones (GH) secreted by the anterior pituitary, their primary target (s), & their effects
Primary Targets: liver, muscle, bone & adipose tissue
Effects: Height and helping build bones & muscles
Adrenocorticotropic Hormones (ACTH) secreted by the anterior pituitary, their primary target (s), & their effects
Primary Targets: adrenal cortex
Effects: Stimulate adrenal glands to release cortisol
Thyroid-Stimulating Hormones (TSH) secreted by the anterior pituitary, their primary target (s), & their effects
Primary Targets: Thyroid Glands
Effects: Stimulate the production & release of thyroid hormones
Prolactin Hormones secreted by the anterior pituitary, their primary target (s), & their effects
Primary Targets: Mammary Gland
Effects: Promoting the growth of mammary alveoli and stimulating the synthesis of milk components like lactose, casein, and lipids within the breast tissue
Follicle-Stimulating Hormones (FSH) secreted by the anterior pituitary, their primary target (s), & their effects
Primary Targets: Granulosa & Sertoli Cells
Effects: Reproduction for both sexes
Luteinizing Hormones (LH) secreted by the anterior pituitary, their primary target (s), & their effects
Primary Targets: Gonads
Effects: Stimulating the production of sex hormones
Locations of the Hypothalamus, Anterior Pituitary, and Posterior Pituitary,
including the Portal System used by the Anterior Pituitary
-The hypothalamus is directly above the pituitary gland
-The anterior (front) pituitary and posterior (back) pituitary are located at the base of the brain
-The Anterior pituitary is connected to the hypothalamus via the hypophyseal portal system
Negative Feedback for Complex Endocrine Pathways vs. Simple Endocrine Pathways
-Complex: a hormone produced by a target gland acts to inhibit the further secretion of hormones at earlier stages in the pathway
-Simple: a hormone level in the bloodstream becomes too high, it signals the gland that produced it to decrease further production of that hormone
The Role of Hypothalamic Neurohormones in Secreting Anterior Pituitary Hormones
Command signals that directly stimulate or inhibit their release
Adrenal Cortex: Anatomy, Location, Type of Hormones Secreted, Control Pathways for Hormone Secretion, Primary Targets, & Effects
-Anatomy: Zona glomerulosa (outer layer), zona fasciculata (middle layer), & zona reticularis (inner layer)
-Location: Outer part of the both adrenal glands
-Type of Hormones Secreted: Steroid hormones
-Control Pathways for Hormone Secretion: Hypothalamic pituitary adrenal (HPA) axis
-Primary Targets: ACTH
-Effects: Produce hormones that affect metabolism, blood pressure, & sex characteristics
Hormonal Response to Stress
The release of epinephrine and norepinephrine for short-term stress, and cortisol for long-term stress
Consider how a disruption to the structure or function of a component of an endocrine
pathway could influence the secretion (hyper or hypo) of a hormone. Consider the role of
negative feedback in these situations and how hyper or hypo secretion of a hormone would
influence the secretion of its trophic hormones.
The wrong signaling could occur and the negative feedback loop can be disruptive, causing abnormal hormone levels
Four Main Ways Hormones Interact with each other
-Additive
-Synergism
-Permissiveness
-Antagonism
Additive
When two or more hormones combine to have an effect (1 + 1 = 2)
Synergism
When two or more hormones
combine to yield an effect that is
greater than additive (1 + 1 = 5)
Permissiveness
A hormone can only exert its effect when another hormone is present
Antagonism
When two hormones have opposite physiological effects
