Role of CXCR2 in cigarette smoke-induced lung inflammation.

It has been hypothesized that the destruction of lung tissue observed in smokers with chronic obstructive pulmonary disease and emphysema is mediated by neutrophils recruited to the lungs by smoke exposure. This study investigated the role of the chemokine receptor CXCR2 in mediating neutrophilic inflammation in the lungs of mice acutely exposed to cigarette smoke. Exposure to dilute mainstream cigarette smoke for 1 h, twice per day for 3 days, induced acute inflammation in the lungs of C57BL/6 mice, with increased neutrophils and the neutrophil chemotactic CXC chemokines macrophage inflammatory protein (MIP)-2 and KC. Treatment with SCH-N, an orally active small molecule inhibitor of CXCR2, reduced the influx of neutrophils into the bronchoalveolar lavage (BAL) fluid. Histological changes were seen, with drug treatment reducing perivascular inflammation and the number of tissue neutrophils. beta-Glucuronidase activity was reduced in the BAL fluid of mice treated with SCH-N, indicating that the reduction in neutrophils was associated with a reduction in tissue damaging enzymes. Interestingly, whereas MIP-2 and KC were significantly elevated in the BAL fluid of smoke exposed mice, they were further elevated in mice exposed to smoke and treated with drug. The increase in MIP-2 and KC with drug treatment may be due to the decrease in lung neutrophils that either are not present to bind these chemokines or fail to provide a feedback signal to other cells producing these chemokines. Overall, these results demonstrate that inhibiting CXCR2 reduces neutrophilic inflammation and associated lung tissue damage due to acute cigarette smoke exposure.

The late pubertal cascade in perimenarchial monkeys: onset of asymmetrical ovarian estradiol secretion and bioassayable luteinizing hormone release.

Changes in ovarian function and pituitary gonadotropin secretion were studied in perimenarchial rhesus monkeys. Even in the premenarchial interval, a modest degree of asymmetrical ovarian estradiol secretion was evident. A progression toward marked asymmetry of ovarian function continued after menarche, culminating in ovulatory menstrual cycles with intermenstrual intervals of approximately 28 days. Among postmenarchial monkeys manifesting five or fewer episodes of overt uterine bleeding, no ovulations were detected despite estradiol elevations similar to those of adults in the midfollicular phase. Soon thereafter, among individuals usually having more than 10 menses, the first ovulations were likely to be achieved. The initiation of estrogen-positive feedback, driving the surge modes of gonadotropin secretion, was accompanied by the onset of a striking disparity between bioassayable vs. immunoassayable LH in the circulation. In this report we describe a cascade of late pubertal events including: 1) the gradual establishment of cyclic asymmetrical ovarian estrogen secretion in the perimenarchial interval, 2) increased pituitary responsiveness to GnRH, 3) quantitative and qualitative changes in the pulsatile secretion of pituitary gonadotropins, and 4) an enhancement of bioassayable LH secretion, especially during the preovulatory surge.

Asymmetrical ovarian function during recruitment and selection of the dominant follicle in the menstrual cycle of the rhesus monkey.

Despite similar exposure to pituitary gonadotropins by perfusion of both ovaries with the same peripheral blood, only 1 of the 2 ovaries sponsors the single dominant follicle in the typical menstrual cycle. In the present study was examined the initiation of asymmetrical ovarian function during recruitment and selection of the dominant follicle in the primate ovarian cycle by comparison of steroid hormones in the ovarian venous effluent. Thirty-four adult female rhesus monkeys were selected because of high estimated fertility based on their reproductive performance. These monkeys underwent laparotomy for ovarian inspection and collection of ovarian venous blood on 1 of days 1, 3, 5, 7, 9, and 11 after the onset of menses. In addition, femoral blood was collected daily. Repeat laparotomies were performed in the midluteal phase to assess the location of the functional corpus luteum. Concentrations of 17 beta-estradiol, androstenedione, and progesterone were determined in all sera, as well as LH and FSH in peripheral sera, by RIA. In all, 17 of 19 ovulatory monkeys manifested clear asymmetry of 17 beta-estradiol 5 days before the LH/FSH midcycle surges. Often, asymmetry of androstenedione levels was not apparent until 3 days before the midcycle gonadotropin surge. Uniformly, in ovulatory monkeys, the ovary associated with significantly greater concentrations of 17 beta-estradiol and androstenedione in ovarian venous serum ultimately bore the functional corpus luteum observed in the midluteal phase and confirmed by elevated progesterone in peripheral serum. We interpret these findings to indicate that asymmetrical ovarian steroid secretion, especially of 17 beta-estradiol, may be among the earliest indicators that the dominant follicle, or at least the ovary destined to bear it, is already selected by 5 days before the preovulatory FSH/LH surge in the typical menstrual cycle.

Pregnancy diagnosis in squirrel monkeys: hemagglutination test, radioimmunoassay, and bioassay of chorionic gonadotropin.

The Nonhuman Primate Pregnancy Test may be useful for diagnosis of pregnancy in squirrel monkeys between 40 and 60 days in pregnancy. However, single determinations have an inherent 10% risk of false negative responses caused by low chorionic gonadotropin levels; thus, initial negative test responses should be followed within one week by an independent confirmatory test. Preliminary results with this hemagglutination inhibition test compare favorably with bioassay and may be useful, in conjunction with conventional uterine palpation, for diagnosis of pregnancy in squirrel monkeys.

Pregnancy diagnosis in the orangutan (Pongo pygmaeus) using the subhuman primate pregnancy test kit.

A determination was made of the gestational interval over which the Subhuman Primate Pregnancy Test, a hemagglutination inhibition test for urinary chorionic gonadotropin, accurately indicated conception and the continuation of pregnancy in an orangutan (Pongo pygmaseus). The initial positive diagnostic test response occurred about 8 months before parturition and positive responses continued throughout gestation. A test made one day after parturition was positive indicative of some residual urinary chorionic gonadotropin. Tests made 3 days after parturition and later were negative.

Diagnosis of pregnancy in chimpanzees using the nonhuman primate pregnancy test kit.

The usefulness of The Nonhuman Primate Pregnancy Test kit for diagnosis of pregnancy in chimpanzees was determined. This hemagglutination inhibition test for urinary chorionic gonadotropin accurately indicated conception by positive responses in 151 to 153 specimens collected between 20 and 133 days after the estimated day of fertilization. The rate of false positive responses did not exceed 1%.

PIP: This hemagglutination inhibition test employs an antiserum (H-26), to the beta-subunit of ovine luteinizing hormone which is highly cross-reactive with urinary chorionic gonadotropins of both Old World and New World primates. The test has been found to be reliable between Pregnancy Days 18-23 in macaques, Days 17-30 in baboons, and Days 25-70 in marmosets. In this study, 365 urine specimens from 8 pregnant chimpanzees and 2 nonpregnant females were examined. From Day 20 of pregnancy onward, 151 of 153 specimens gave positive test results. The 2 negative tests were regarded as false negative responses. Only 1 false positive test was found among 161 urine specimens from nonpregnant chimpanzees. Inconclusive results were less than 3%. Diluting the urine specimen with deionized water, 1 part urine to 2 parts water, resolved these inconclusive responses. After the 19th week of pregnancy the incidence of negative tests increased markedly. The test before Day 20 or after Day 133 is not recommended. Test kits can be obtained at no cost by writing to the Hormone Distribution Officer, Office of the Director, NIAMDD, Building 31A, Room 9A47, National Institutes of Health, Bethesda, Maryland 20014.