PMID- 9780318
OWN - NLM
STAT- MEDLINE
DCOM- 19981222
LR  - 20190512
IS  - 0006-3363 (Print)
IS  - 0006-3363 (Linking)
VI  - 59
IP  - 5
DP  - 1998 Nov
TI  - Excitatory amino acid regulation of gonadotropin secretion in prepubertal heifer 
      calves.
PG  - 1124-30
AB  - The mechanisms controlling the pulsatile release of gonadotropins in prepubertal 
      heifers are not completely understood. We examined the role of excitatory amino 
      acid neurotransmitters, via activation of N-methyl-D-aspartate (NMDA) receptors, 
      in the control of pulsatile LH and FSH release during prepubertal development in 
      heifers. Hereford heifer calves received 4.7 mg/kg of N-methyl-D,L-aspartic acid 
      (NMA), a potent NMDA receptor agonist (n = 5, i.v.), or saline (n = 5, i.v.), as 
      single doses, at 4, 8, 12, 24, 36, and 48 wk of age. Blood samples were collected 
      every 15 min, for 1 h before and 9 h after injection, on the days of treatment. 
      Injection of NMA resulted in an acute release of LH (p < 0.001) in 0, 3, 3, 4, 5, 
      and 5 calves (p < 0.01) and of FSH (p < 0.001) in 0, 1, 2, 4, 3, and 2 calves at 
      4, 8, 12, 24, 36, and 48 wk of age, respectively. The peak response of LH and FSH 
      release to NMA was at 15 min posttreatment, and these peak responses were highest 
      at 36 wk of age (p < 0.05). We suggest that neuroexcitatory amino acids, through 
      NMDA receptors, are involved in prepubertal development of LH and FSH secretion 
      in heifer calves.
FAU - Honaramooz, A
AU  - Honaramooz A
AD  - Department of Veterinary Physiological Sciences, Western College of Veterinary 
      Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4.
FAU - Chandolia, R K
AU  - Chandolia RK
FAU - Beard, A P
AU  - Beard AP
FAU - Rawlings, N C
AU  - Rawlings NC
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Biol Reprod
JT  - Biology of reproduction
JID - 0207224
RN  - 0 (Excitatory Amino Acids)
RN  - 0 (Receptors, N-Methyl-D-Aspartate)
RN  - 6384-92-5 (N-Methylaspartate)
RN  - 9002-67-9 (Luteinizing Hormone)
RN  - 9002-68-0 (Follicle Stimulating Hormone)
SB  - IM
MH  - Aging
MH  - Animals
MH  - Cattle/*physiology
MH  - Excitatory Amino Acids/*pharmacology
MH  - Female
MH  - Follicle Stimulating Hormone/*metabolism
MH  - Luteinizing Hormone/*metabolism
MH  - N-Methylaspartate/pharmacology
MH  - Periodicity
MH  - Receptors, N-Methyl-D-Aspartate/drug effects/physiology
MH  - Sexual Maturation
EDAT- 1998/10/22 00:00
MHDA- 1998/10/22 00:01
CRDT- 1998/10/22 00:00
PHST- 1998/10/22 00:00 [pubmed]
PHST- 1998/10/22 00:01 [medline]
PHST- 1998/10/22 00:00 [entrez]
AID - 10.1095/biolreprod59.5.1124 [doi]
PST - ppublish
SO  - Biol Reprod. 1998 Nov;59(5):1124-30. doi: 10.1095/biolreprod59.5.1124.