The effect of ovine pineal compounds prepared under red or green light on the activity of male rat anterior pituitariesin vitro

Abstract

A high molecular weight fraction XM100R (MW A 100,000) was prepared by ultrafiltration from ovine pineals using two different extraction methods under red light conditions (lambda greater than 600 nm). This fraction stimulates the release of radioimmunologically active luteinizing hormone (LH) of anterior pituitaries in vitro. The ultrafiltration fraction PM30R (MW greater than 30,000 and less than 100,000) was found to be radioimmunologically active only when the "Bensinger" extraction procedure was applied. However, when comparable fractions were prepared under green light and incubated with half-pituitaries, all the incubation media of the ultrafiltrated fractions, XM100R, PM30R, PM10R (MW greater than 10,000 and less than 30,000) UM2R (MW greater than 1000 and less than 10,000), UM05R (MW greater than 500 and less than 1000) and UM05F (MW greater than 500), reacted with anti-LH. This may mean that under green light conditions the high molecular weight ovine pineal compounds in XM100R are disintegrated and/or split up into small molecules which can stimulate the release of LH, or crossreact with the anti-LH serum.

Studies on a high molecular weight luteinizing hormone release stimulating factor of the ovine pineal gland

“…Anterior pituitaries of adult male Wistar rats were divided in two halves and each hemipituirary was incubated at 37 ~ in 0.5 ml of Krebs Ringer medium (Slama-Sc6mama et al, 1985). After 1 h of preincubation time, media were renewed and incubated again for a 1 h period at 37 ~ Subsequently, the glands were randomly divided in groups of six hemipituitaries (one per tube) and transferred to fresh medium containing the ovine pineal material.…”

“…Other investigators were unable to detect immunologically LHRH-like compounds in the pineal gland (Carson et al, 1977;P6vet et al, 1980). Slama-Sc6mama et al (1985) observed a stimulatory effect of high M r substances (100 to 300 K) of fractionated extracts from ovine pineal glands on the release of immunoassayable luteinizing hormone (LH) of rat anterior pituitaries in short-term culture. The present paper communicates the attempts to study further the properties of high Mr ovine pineal proteic substances showing a stimulatory effect on the levels of gonadotropins in the medium of either cultured pituitary cells (De Jong et al, 1978) or anterior hemipituitaries in short-term culture (Slama-Sc6mama et al, 1985).…”

“…Slama-Sc6mama et al (1985) observed a stimulatory effect of high M r substances (100 to 300 K) of fractionated extracts from ovine pineal glands on the release of immunoassayable luteinizing hormone (LH) of rat anterior pituitaries in short-term culture. The present paper communicates the attempts to study further the properties of high Mr ovine pineal proteic substances showing a stimulatory effect on the levels of gonadotropins in the medium of either cultured pituitary cells (De Jong et al, 1978) or anterior hemipituitaries in short-term culture (Slama-Sc6mama et al, 1985). In particular attention was drawn to the question whether the effects observed, were due to (non-)specific interferences of pineal proteins with antibodies raised against gonadotropins or whether these effects represented (a) gonadotropin releasing factor(s) from ovine pineal tissue.…”