アドレノコルチコトロプホルモンは,下垂体から脳に直接輸送されることがあります
まとめ
アドレノコルチオトロプホルモン (ACTH) のような下垂体ホルモンは,脳に直接到達する可能性があります. 羊のACTH値が上昇した
科学分野:
- 神経内分泌学の神経内分泌学
- 生理学 生理学とは
背景:
- pituitary ホルモンの脳への直接的な輸送は,議論の余地のある話題です.
- この経路を理解することは,脳の機能と疾患の研究に不可欠です.
研究 の 目的:
- pituitary ホルモンが脳に直接送られるという仮説を検証する.
- 脳静脈血中のアドレノコルチオトロピクホルモン (ACTH) 濃度を測定するために.
主な方法:
- 覚醒している羊の動脈,サギタルシヌス,動脈から同時に血液を採取する.
- ACTHの分泌を刺激するために,発作の電気誘導.
- 発作後の正確な間隔で血ACTH濃度分析.
主要な成果:
- 発作後,サギタルシナスのACTHレベルは,しばしば動脈と動脈のレベルを超えました.
- これは,下垂体から派生したACTHが脳毛細血管の床に入り,サギタルシヌス経由で脱出することを示唆しています.
- ハイポフィセクトミーを受けた羊では,発作後のサギタルシヌスACTHの上昇は,脳由来ACTHの放出を示唆した.
結論:
- 証拠は,脳毛細血管経由で脳へ垂体ACTHの直接送達を支持しています.
- 脳自体もACTHまたはACTHのような物質を放出する可能性があります.
関連する概念動画
Hypothalamic-Pituitary Axis
The response to stress—be it physical or psychological, acute or chronic—involves activation of the Hypothalamic-Pituitary-Adrenal (HPA) axis. The HPA axis is part of the neuroendocrine system because it involves both neuronal and hormonal communication. Its function is to regulate homeostatic systems—metabolic, cardiovascular, and immune—providing the necessary means to respond to a stressor.
Regulation of Hormone Secretion
Regulation of hormone secretion is a finely tuned orchestration driven by various types of stimuli, encompassing neural, humoral, and hormonal signals. Environmental cues instigate neural stimuli, where action potentials traverse nerve fibers to reach their designated targets. An illustrative scenario is the body's response to stress, wherein the sympathetic nervous system releases epinephrine from the adrenal glands, inducing the well-known 'fight or flight' reaction.
Humoral stimuli,...
Humoral stimuli,...
The Pituitary Gland
The pituitary is a small endocrine organ in the sphenoid bone under the hypothalamus. Primarily, the pituitary in adults has two distinct anatomical and functional regions— the anterior and posterior lobes. During human fetal development, a third pituitary gland region called the pars intermedia atrophies and disappears. However, some of its cells migrate and exist adjacent to the anterior pituitary in adults.
Hormones of the Pituitary Gland
The small, pea-sized pituitary gland is located at the base of the brain. It is crucial in regulating various bodily functions, from growth to reproduction. The gland is divided into the anterior lobe and the posterior lobe. The secretory cell clusters in the pars distalis of the anterior pituitary lobe are controlled by hypothalamic regulators and synthesize six primary hormones.
The most abundantly secreted hormone from the anterior lobe is the growth hormone, which controls overall growth by...
The most abundantly secreted hormone from the anterior lobe is the growth hormone, which controls overall growth by...
Hormones of the Adrenal Glands
Adrenal hormones play a pivotal role in maintaining the body's electrolyte balance and orchestrating responses to stress, showcasing the intricate functions of the adrenal cortex and medulla.
The adrenal cortex, a powerhouse of hormone synthesis, generates over two dozen corticosteroid hormones. The zona glomerulosa produces mineralocorticoids, exemplified by aldosterone, influencing the electrolyte composition of body fluids. The synthesis of glucocorticoids such as cortisol and corticosterone...
The adrenal cortex, a powerhouse of hormone synthesis, generates over two dozen corticosteroid hormones. The zona glomerulosa produces mineralocorticoids, exemplified by aldosterone, influencing the electrolyte composition of body fluids. The synthesis of glucocorticoids such as cortisol and corticosterone...
Cushing Syndrome II: Pathophysiology
Cortisol production is normally governed by the hypothalamic–pituitary–adrenal (HPA) axis, which maintains hormonal balance through tightly regulated feedback mechanisms. Disruption of this regulatory system is central to the development of Cushing syndrome, whether the excess cortisol originates from external medications or internal pathology. Persistent cortisol elevation alters metabolism, immune function, and endocrine signaling, producing the characteristic clinical features of the...


