Reproductive Physiology Flashcards
Outline the regulation of reproductive processes by Neural control.
- Nerves release neurotransmitters directly onto the target tissue
- Usually operates via spinal cord
Outline the regulation of reproductive processes via ‘Neuroendocrine control’.
- Combined efforts of nerves and hormones
- Usually operated via spinal cord
- Relies on transort of hormones through circulatory blood
Outline the regulation of reproductive processes via endocrine control.
- Hormones operating independent of the nerves
- Relies on transport of hormones through circulatory blood
Outline the ‘neural reflex’ pathway of regulation of reproductive processes
Stimulus (thermal, tactile, visual) –> Sensory nerve ending –> Afferent neurons –> Spinal cord –> Efferent neurons –> Target tissue –> Neurotransmitters
Outine the pathway (neural/muscular) for ejaculation.
Intromission –> Sensory stimulation of glans penis (temp and pressure –>
Afferent neurons –> spinal cord –> motor neuron –> ischiocavernosus muscle, bulbosporangiosus muscle and urethralis muscle –> expulsion of semen
What is the Neuroendocrine reflex?
Regulation of reproductive processes.
- Sensory nerves synapse with interneurons (I) in the spinal cord
- Efferent neurons travel to the hypothalamus where hypothalamic neurons release neurohormones
- These neurohormones enter the blood and activate target tissues such as the anterior lobe of the pituitary, mammary gland or the epididymis
What is the pathway for milk secretion?
Suckling –> nerve –> hypothalamus –> oxytocin –> lobule (alveolus) –> Milk production
List the Hormones of Reproduction:
Steroid:
- Testosterones
- Oestrogen
- Progesterone
Neuropeptides:
- Gonadotropin-releasing hormone
- Oxytocin
Glycoproteins:
- Follicle stimulation hormone
- Luteinising hormone
Where is the Gonadotropin-releasing hormone produced?
Hypothalamus
Where is the Gonadotropin-releasing hormone released from?
anterior pituitary
What is the role of Gonadotropin-releasing hormone?
Controls the release of gonadotropins (glycoproteins)
What does FSH stimulate?
- Follicular growth in females, hence increases production of oestrogen
- Stimulates Sertoli cells (initiates spermatogenesis) in males
What does luteinising hormone stimulate?
- Induces ovulation of mature follicles, hence formation of C.luteum and production of progesterone
- Stimulates testosterone production in males
What controls the production of sex steroid hormones?
Hypothalamohypophyseal tract via positive and negative feedback of GnRH
Positive = stimulates GnRH release
Negative = suppression of GnRH release
What is the hyothalamohypophyseal tract?
A capillary system connecting the hypothalamus with the anterior pituitary.
What are some physical/physiological responses to testosterone production?
- Male behaviour and aggression
- Spermatogenesis
- Growth of secondary sex glands & muscle
- Development of antlers/horns etc.
What are some effects of Oestrogen production?
- Uterine blood flow
- Growth of uterine endometrial glands
- Secretory activity of oviduct
- Smooth muscle motility
- Sexual receptivity
- Closure of epiphyseal growth plate in bones
- Mammary duct growth