Masahiro Kanazawa1, Mariko Watanabe2, Toshiyasu Suzuki3. 1. Division of Anesthesia, Tokai University Oiso Hospital, 21-1 Gakkyo, Oiso-machi, Naka-gun, Kanagawa, 259-0198, Japan. kanazawa@is.icc.u-tokai.ac.jp. 2. Division of Anesthesia, Tokai University Oiso Hospital, 21-1 Gakkyo, Oiso-machi, Naka-gun, Kanagawa, 259-0198, Japan. 3. Department of Anesthesiology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1143, Japan.
Abstract
PURPOSE: The aim of the present study was to determine whether the ovarian hormones, estrogen and progesterone, had different influences on amino-acid-induced anti-hypothermic effects during general anesthesia. METHODS: Ovariectomized Sprague-Dawley female rats were divided into four groups: those administered 17β-estradiol plus saline or an amino acid mixture (E2-Sal and E2-AA, respectively) and progesterone plus saline or an amino acid mixture (P-Sal and P-AA, respectively). Five weeks after ovariectomy, rats were given either E2 or P and then administered either Sal or AA solution for 180 min during anesthesia with sevoflurane. Rectal temperatures were measured. RESULTS: Rectal temperatures were significantly higher in the E2-AA group than in the E2-Sal group 165 and 180 min after initiating the infusion of the test solutions. However, no significant differences were observed between the P-treated groups. The phosphorylation of 4E-BP1 and S6K1 was significantly greater in the E2-AA group than in the E2-Sal group (P < 0.05, P < 0.001, respectively). In contrast, the phosphorylation of 4E-BP1 was significantly lower in the P-AA group than in the P-Sal group (P < 0.001). CONCLUSIONS: These results suggest that progesterone reduces amino-acid-induced anti-hypothermic effects during general anesthesia.
PURPOSE: The aim of the present study was to determine whether the ovarian hormones, estrogen and progesterone, had different influences on amino-acid-induced anti-hypothermic effects during general anesthesia. METHODS: Ovariectomized Sprague-Dawley female rats were divided into four groups: those administered 17β-estradiol plus saline or an amino acid mixture (E2-Sal and E2-AA, respectively) and progesterone plus saline or an amino acid mixture (P-Sal and P-AA, respectively). Five weeks after ovariectomy, rats were given either E2 or P and then administered either Sal or AA solution for 180 min during anesthesia with sevoflurane. Rectal temperatures were measured. RESULTS: Rectal temperatures were significantly higher in the E2-AA group than in the E2-Sal group 165 and 180 min after initiating the infusion of the test solutions. However, no significant differences were observed between the P-treated groups. The phosphorylation of 4E-BP1 and S6K1 was significantly greater in the E2-AA group than in the E2-Sal group (P < 0.05, P < 0.001, respectively). In contrast, the phosphorylation of 4E-BP1 was significantly lower in the P-AA group than in the P-Sal group (P < 0.001). CONCLUSIONS: These results suggest that progesterone reduces amino-acid-induced anti-hypothermic effects during general anesthesia.
Entities:
Keywords:
Amino acids; Female sex hormones; General anesthesia; Hypothermia
Authors: Joshua C Anthony; Ali K Reiter; Tracy G Anthony; Stephen J Crozier; Charles H Lang; David A MacLean; Scot R Kimball; Leonard S Jefferson Journal: Diabetes Date: 2002-04 Impact factor: 9.461