title: Episodic release of LH in gonadectomized male Japanese quail.
abstract: Blood samples were taken every 15 min (for 4.75 h) from six castrated quail on three separate occasions. The birds were first bled while under short days (comprising 8 h light : 16 h darkness per 24 h; 8L : 16D) and, subsequently, after 1 and 20 days under long days of 16L : 8D. The photoperiodic alteration produced a marked increase in the mean plasma LH concentration of each bird and in four instances the rise was evident after only 1 long day. Pulsatile release patterns were not detected in the plasma LH profiles obtained during exposure to short days or after 1 long day but were pronounced in all of the birds after 20 long days. The peaks (n = 19) occurred on average every 83 +/- 14 (S.E.M.) min and had an amplitude of 12.3 +/- 1.2 micrograms/l. After 35 days under 16L : 8D three of the quail were bled more frequently (every 8 min for 2.5 h), allowing the LH pulses to be measured more precisely. Each pulse was composed of a sudden increase in secretion followed by a slower decrease which lasted for approximately 30 min. The development and functional significance of episodic LH release in the quail is discussed.
mesh_terms: D000818:Animals; D002369:Castration; D003370:Coturnix / Q000502:physiology*; D008027:Light; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D008297:Male; D011784:Quail / Q000502:physiology*
chemical_list: D007986:Luteinizing Hormone