2-十三烷酮对棉铃虫细胞色素P450的诱导作用

将2-十三烷酮按0.005%～0.01%（重量比）的浓度加到棉铃虫人工饲料中，连续诱导3代，测定棉铃虫中肠和脂肪体中细胞色素P450(cyt-P450)含量以及与标准配基（正丁醇、吡啶、苯胺、环己烷）形成的氧化型结合光谱。2-十三烷酮诱导品系的中肠cyt-P450与CO结合光谱的最大吸收峰在449 nm处，脂肪体cyt-P450与CO结合光谱的最大吸收峰在450.7 nm处。中肠cyt-P450除了在450 nm附近存在一个吸收峰外，在通入CO后依次在414、415、418 nm附近出现吸收峰，随后该峰消失，随着时间的推移（第31次扫描）在420 nm处又开始出现一个弱吸收峰。2-十三烷酮诱导品系的中肠、脂肪体cyt-P450与4种标准配基形成的差光谱与对照相比在峰型上存在着不同程度的差异。中肠cyt-P450与正丁醇形成双峰双谷的光谱；脂肪体cyt-P450与正丁醇形成的光谱最大吸收峰在416.61 nm处，波谷在424.91 nm处；中肠cyt-P450和脂肪体cyt-P450与吡啶形成的光谱为典型的Ⅱ型光谱，而与环己烷形成的光谱为不典型Ⅰ型光谱；中肠和脂肪体的cyt-P450与苯胺形成典型的Ⅱ型光谱，最大吸收峰分别在443.30和428.92 nm处，最小吸收分别在402.30和401.00 nm处。

Induction of the cytochrome P450 by 2-tridecanone in Helicoverpa armigera

The induction of the cytochrome P450 (cyt-P450) by 2-tridecanone in cotton bollworm, Helicoverpa armigera (Hübner) larvae was investigated. By mixing 2 tridecanone at low dosages (0.005%～0.01%) for three generations, the content and difference spectra of cyt-P450 interacted with CO and ligands, including pyridine，n-butanol，aniline and cyclohexane, were investigated with cyt-P450 preparation from midgut and fat body of the sixth instar cotton bollworm. The maximal absorption of cyt-P450 interacted with CO was observed around 449 nm for midgut preparation and 450.70 nm for fat body preparation respectively based on 15 to 40 scans in the induction colony, and 449.22 nm for midgut preparation and 449.20 nm for fat body preparation respectively in the control colony. Besides an absorption peak around 449 nm, there were in turn three other absorption peaks around 414, 415, 419 nm in midgut cytochrome P450, thereafter the absorption disappeared, and there was a weak absorption at 420 nm at the thirty-first scan. In the absorption spectrum of cyt-P450 bound with n-butanol, two peaks and two troughs occurred for midgut preparation and one peak and one trough in fat body preparation. The maximal absorption peaks were at 380.10 nm, 415.02 nm for midgut preparation and 416.61 nm for fat body preparation, while the absorption troughs were at 395.02 nm, 423.24 nm for midgut preparation and 424.91 nm for fat body preparation. Characteristic type Ⅱ spectrum occurred with cyt-P450 bound with pyridine, for midgut preparation with a maximal absorption at 425.57 nm and a trough at 395.48 nm; for fat body preparation with a maximal absorption at 422.19 nm and a trough at 415.90 nm. Uncharacteristic type Ⅰ spectrum occurred with cyt-P450 bound with cyclohexane, for midgut preparation with maximal absorption peaks at 378.00 nm and 448.12 nm; for fat body preparation with the maximal absorption peaks at 380.00 nm and 434.04 nm. Type Ⅱ spectrum occurred with cyt-P450 bound with aniline, for midgut preparation with a maximal absorption at 443.30 nm and a trough at 402.30 nm; for fat body preparation with a maximal absorption at 428.92 nm and a trough at 401.00 nm.