Neural regulation of LHRH

Luteinizing hormone-releasing hormone (LHRH) is a neurohormone produced in the hypothalamus which regulates reproduction [1]. LHRH neurons project to the median eminence and release LHRH in a pulsatile manner into the hypophyseal portal system [2]. This stimulates the anterior pituitary to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which act on the gonads to support gametogenesis and sex steroid secretion [3]. Precise regulation of LHRH pulsatility is critical for maintaining normal reproductive capacity in both males and females [4][5].

The neural regulation of LHRH involves stimulatory norepinephrine input as well as inhibitory dopamine, GABA, and opioid input [6]. Norepinephrine binds to α1 receptors on LHRH neurons while dopamine acts via D2 receptors to decrease cAMP production [4]. GABA and opioids like β-endorphin provide additional inhibition by acting on GABAA and μ-opioid receptors, respectively [6]. The balance between these neural inputs generates the appropriate pattern of LHRH pulses needed for gonadotropin release and downstream reproductive processes like spermatogenesis, ovulation, and sexual behavior [4][5]. Disruption of LHRH secretion can lead to infertility and other reproductive disorders [6].

Sources:

  1. Color Atlas of Physiology by Silbernagl S., Despopoulos A. (2001). Thieme.
  2. Affective Neuroscience: The Foundations of Human and Animal Emotions by Panksepp, J. (1998). Oxford University Press.
  3. Biological Psychology, 3rd Edition by Toates, F. M. (2009). Pearson Education.
  4. The Archaeology of Mind: Neuroevolutionary Origins of Human Emotions by Panksepp, J. & Biven, L. (2012). W. W. Norton & Company.
  5. Strickland, B. R. (Ed.). (2001). Gale encyclopedia of psychology (2nd ed.). Gale Group.
  6. Foundations of Biopsychology by Wickens, A. (2015). Routledge.