We present temperature-dependent fluorescence quantum yield and lifetime measurements on the LH-1 and LH-2 complexes of Rhodobacter sphaeroides and on the isolated B820 subunit of Rhodospirillum rubrum. From these measurements the superradiance is calculated, which is related to the delocalization of excitations in these complexes. In the B820 preparation we find a radiative rate that is 30% hi...

Seven yearling Holstein bulls were given 0, 20, 40, 60, 80, 100 and 200 micrograms NIH-LH-B9 during a 7-day complete Latin square design experiment. Treatments were administered via jugular cannulas at 0900 hr, and blood was collected at 60, 30 and 0 min before treatment, at 15-min intervals for 3 hr after treatment and at 30-min intervals from 3 to 7 hr after treatment. Luteinizing hormone (LH...

Gonadotropins are heterodimers consisting an alpha chain (Cgα) and a beta chain. Interestingly, presence of complicated LH-β transcripts in rat testis was accidently found; testicular LH-β transcripts were confined in seminiferous tubules to spermatids, and the translated products were localized in the elongated spermatids. We hypothesized that mouse testis has potential to produce the tissue s...

Plasma LH and testosterone levels did not differ significantly between high and low fertility rams before or after sexual stimulation (ejaculation or teasing). Repeated stimulation caused significant elevation of mean plasma LH and an almost significant rise in testosterone concentration. Plasma testosterone peaks followed those of LH after 30-60 min. A single sexual stimulation did not always ...

The present studies were conducted to determine whether luteinizing hormone (LH), a hormone which increases intracellular cAMP, also increases "second messengers" derived from inositol phospholipid hydrolysis in isolated bovine luteal cells. In luteal cells prelabeled with 32PO4, LH provoked increases in labeling of phosphatidic acid, phosphatidylinositol, and polyphosphatidylinositol (PIP). No...

BACKGROUND/AIM In the colorectum, lymphoid follicles hyperplasia (LH) is sometimes observed as small, round, yellowish-white nodules. The novel image-enhanced endoscopy system named blue laser imaging (BLI) provides enhanced the contrast of surface vessels using lasers for light illumination. We investigated the endoscopic features of LH observed by using BLI endoscopy and its association with ...

As a first step of investigating male predominance of bladder cancer incidence, we have studied relationships between rat bladder carcinogenesis, induced by BBN, and changes of pituitary-testicular axis, induced by a LH-RH analogue. The rats were divided into the following five groups. The first group (Age matched control group) was given normal drinking water for 30 weeks. The 2nd group (BBN g...

BACKGROUND To test the effects of progressively decreasing dosages of exogenous LH we combined various amounts of HMG, containing FSH, LH and HCG, and highly purified (HP) FSH to treat 120 GnRH agonist-suppressed infertile female patients as candidates for controlled ovarian stimulation (COS). METHODS Subjects were randomly assigned to four treatment groups that received the following daily i...

It is not practical to quantitate gonadotropin in the blood of normal men and women by utilizing bioassays. We have developed a method for sensitive, precise, and specific radioimmunoassay of luteinizing hormone (LH) in human serum or plasma. Antisera were developed against human chorionic gonadotropin, and one of these was selected for extensive cross-reaction with human LH. Highly purified LH...

As the expression of the LH receptor (LH-R) in granulosa cells is thought to be associated with later stages of folliculogenesis, this study was undertaken to evaluate the presence of LH-R mRNA as a suitable marker for developmental competence of oocytes. Granulosa cells and cumulus-oocyte complexes (COCs) were recovered from cows that had received ovarian stimulation. The COCs were subjected t...