The presence of a pregnenolone-binding factor in the copulatory organ of the migratory locust, Locusta migratoria migratorioides R. & F.

The presence of binding sites for nonecdysteroid steroids was investigated in the cytosol of several tissues of the migratory locust, Locusta migratoria migratorioides. Binding of androgens was not observed. Most tissues, however, showed nonsaturable binding of estrogens and in some tissues saturable progestin binding could be demonstrated. A pregnenolone binder, that was found to be present in the male copulatory organ, was further studied. It showed a dissociation constant of 4.4 (+/- 1.6) X 10(-8) M. This is the first report of a nonecdysteroid steroid-binding factor in an insect tissue.

Study of the metabolism of steroids in larvae of the fleshfly Sarcophaga bullata.

1. Larvae of the fleshfly Sarcophaga bullata were injected with several 3H C21 and C19 steroids. After different incubation times, the larvae were homogenized and the metabolites were extracted and fractionated by Sephadex LH 20-, paper- and thin-layer chromatography. The chromatographic mobility of the labeled zones was compared with that of standard steroids. 2. Progesterone and 17 alpha-hydroxypregnenolone were metabolized to 17 alpha-hydroxyprogesterone. Androstenedione, 17 alpha-hydroxyprogesterone and dehydroepiandrosterone were converted to testosterone. Transformation of pregnenolone to progesterone or 17 alpha-hydroxypregnenolone was not observed. 3. C21 or C19 steroid formation from cholesterol could not be demonstrated. 4. Sixteen metabolites, different from all our standard substances have been found. Their structure remains to be elucidated.

Urinary indices in acute interstitial nephritis.

Nine patients with biopsy-proven acute interstitial nephritis (AIN) were analyzed for their urinary indices, determined on the basis of the first urinary sample upon admission, before any therapeutic intervention. Isosthenuria was present in all patients with a mean urinary osmolality of 283 +/- 48 mOsm/l and a urine/plasma osmolality ratio of 0.9 +/- 0.1. Urinary sodium was more than 40 mEq/l in 8 out of the 9 patients studied. The other urinary indices studied were indicative for both prerenal and intrinsic renal disease.

Identification of nonecdysteroid steroids in hemolymph of both male and female Astacus leptodactylus (Crustacea) by gas chromatography-mass spectrometry.

The O-pentafluorobenzyloxime (OPFB)-heptafluorobutyrylester (HFB) derivatives of hemolymph steroid extracts from both male and female Astacus leptodactylus were subjected to negative ion chemical ionization and capillary gas chromatography-mass spectrometry (NCI/GC-MS). Five nonecdysteroid steroids, namely pregnenolone, 17 alpha-hydroxypregnenolone, testosterone, cholesterol, and 6 beta-hydroxyprogesterone were identified. With selected ion monitoring (SIM), indications were found for the presence of four more steroids: androstenedione, 5 alpha-dihydrotestosterone, 11-ketotestosterone, and 11 beta-hydroxytestosterone. The presence of 6 beta-hydroxyprogesterone could only be demonstrated in the female hemolymph. With the technique used, dehydroepiandrosterone, progesterone, 17 alpha-hydroxyprogesterone, and estrogens could not be detected in male or female hemolymph extracts.

Identification of testosterone and progesterone in hemolymph of larvae of the fleshfly Sarcophaga bullata.

Testosterone- and progesterone-like substances were detected by radioimmunoassay (RIA) in chromatographed extracts of hemolymph from larvae of Sarcophaga bullata (S.B.). Gas chromatographic (GC) analysis after heptafluorobutyric acid (HFBA) derivation of hemolymph extracts, purified by paper and silica gel column chromatography, showed a peak in the GC recordings with the same retention time as the HFBA derivative of pure testosterone. A testosterone concentration of 92 ng/100 ml hemolymph was found by GC; the concentration of progesterone, calculated on the basis of the RIA, was about two times higher. After preparing the o-pentafluorobenzyloxime (OPFB)-heptafluorobutyryl ester (HFB) derivatives of the hemolymph extracts, negative ion chemical ionization capillary gas chromatography-mass spectrometry (NCI/GC-MS) proved that hemolymph of larvae of the fleshfly Sarcophaga bullata indeed contains testosterone and progesterone. Several metabolites and precursors of the latter compounds could also be detected during the NCI/GC-MS analyses. Estrogens could not be traced by any of the methods we used. This is the first time that these steroids have been identified in insect hemolymph. These results add interesting perspectives for comparative endocrinology.

Metabolism of injected [3H]ecdysone in male Sarcophaga bullata (Diptera).

Within 30 min after injection, [3H]ecdysone was rapidly partially metabolized to ecdysterone and other ecdysteroids. After 8 hr most (99%) of the tritiated material had disappeared from the hemolymph. In testes, the predominant ecdysteroid appeared to be ecdysterone but no accumulation occurred. Comparison of the dynamics of the ecdysone metabolism in abdomens and head-thorax sections showed that in the head-thorax ecdysterone was the major component, whereas in abdomens the major metabolites were highly polar products (HPP). However, the total amount of label was nearly the same in both parts. Two groups of HPP have been isolated from the abdomen fractions without testes: HPP B and HPP C. Only HPP B could be hydrolyzed by enzymes and seemed at least to contain glucuronides, beta-glucosides, and sulfate conjugates. After 4 hr most of the tritiated ecdysteroids were found in the fecal material. No male-specific metabolites have been discovered.