뒤로P: Chapter 11
스터디 가이드 - 스마트 노트
자료에 맞춘 맞춤형 노트, 핵심 정의, 예시, 맥락을 확장해 제공합니다.
Section 1: Introduction of Endocrine Glands
Overview of Endocrine Glands
The endocrine system is composed of ductless glands that secrete hormones directly into the bloodstream. These hormones regulate a wide range of physiological processes by acting on target cells equipped with specific receptors.
Endocrine vs. Exocrine Glands: Endocrine glands release hormones into the blood, while exocrine glands secrete substances through ducts to external or internal surfaces.
Target Specificity: Hormones affect only those cells that possess the appropriate receptors.
Other Hormone-Secreting Organs: In addition to classic endocrine glands, organs such as the heart, liver, kidneys, and adipose tissue also secrete hormones.
Neurohormones: Specialized hypothalamic cells secrete neurohormones, which play a key role in integrating the nervous and endocrine systems.
Functions: Hormones regulate metabolism, growth, reproduction, and homeostasis.
Major Endocrine Glands and Their Hormones
Gland/Hormone | Primary Target Organs | Primary Effects |
|---|---|---|
Leptin | Hypothalamus | Suppresses appetite |
Glucocorticoids (mainly cortisol) | Liver and muscles | Promote glucose metabolism, anti-inflammatory effects |
Mineralocorticoids (mainly aldosterone) | Kidneys | Promote Na+ retention, K+ excretion, water balance |
Epinephrine | Heart, bronchioles, blood vessels | Stimulates fight-or-flight response |
Antidiuretic hormone (ADH) | Kidneys and blood vessels | Promotes water retention, vasoconstriction |
Insulin | Liver, skeletal muscle, adipose tissue | Stimulates cellular uptake of glucose, lowers blood glucose |
Parathyroid hormone (PTH) | Bone, small intestine, kidneys | Increases blood Ca2+ concentration |
Melatonin | Hypothalamus, anterior pituitary | Regulates circadian rhythms |
Thyroxine (T4) and triiodothyronine (T3) | Most organs | Increase basal metabolic rate, essential for growth and development |
Section 2: Pituitary Gland
2.1 Structure of Pituitary Gland
The pituitary gland, often called the "master gland," is attached to the hypothalamus by the infundibulum. It is divided into two main lobes, each with distinct origins and functions:
Anterior Lobe (Adenohypophysis): Glandular tissue derived from the embryonic mouth (Rathke's pouch). It consists of the pars distalis and pars tuberalis and secretes trophic hormones that regulate other endocrine glands.
Posterior Lobe (Neurohypophysis): Nervous tissue derived from a down-growth of the brain, consisting mainly of the pars nervosa. It stores and releases hormones produced by the hypothalamus.
*Additional info: The pituitary gland is protected within the sella turcica of the sphenoid bone.*
