Cardiac ischemia model for +Gz using miniature swine and baboons.

Background: Military aircrew with minimal coronary artery disease (MCAD) may be restricted from flying high-performance aircraft due to possible ischemia during high +Gz. An animal model is presented to provide ischemia data for a more informed decision.

Methods: There were 18 swine that were placed on a high cholesterol/high fat diet for up to 57 wk.

The phosphodiesterase 3 inhibitor ORG 9935 inhibits oocyte maturation in the naturally selected dominant follicle in rhesus macaques.

Background: The study was conducted to determine whether the phosphodiesterase (PDE) 3 inhibitor ORG 9935 prevents the resumption of meiosis in primate oocytes during natural menstrual cycles.

Study Design: Regularly cycling adult female macaques (n=8) were followed during the follicular phase and then started on a 2-day treatment regimen of human recombinant gonadotropins to control the timing of ovulation. Monkeys received no further treatment (controls) or ORG 9935.

Evaluation of the vervet (Clorocebus aethiops) as a model for the assisted reproductive technologies.

The vervet monkey was evaluated as a primate model for use in assisted reproductive technologies (ARTs). Eight adult female vervets were hormonally monitored for their potential use as egg donors and those six females displaying regular menstrual cycles were subjected to controlled ovarian stimulation with recombinant human gonadotropins. Three animals failed to respond while laparoscopic follicular aspiration was performed on the other three females at 27-30 h post-human chorionic gonadotropin administration.

Characteristics and regulation of the ovarian cycle in vervet monkeys (Chlorocebus aethiops).

This study was designed to evaluate the timecourse of ovarian and pituitary endocrine events throughout the menstrual cycle in the vervet monkey, and whether circulating luteinizing hormone (LH) or the uterus regulates the functional lifespan of the vervet corpus luteum. Daily saphenous blood samples were collected from adult females (1) during spontaneous menstrual cycles (n = 7), and (2) during cycles in which a gonadotropin-releasing hormone antagonist (acyline) was administered for 3 days at midluteal phase (n = 3), and (3) for 30 days following recovery from hysterectomy (n = 4). Estradiol (E) and progesterone (P) levels were assayed using electrochemoluminescent assays.

Assessment of menstruation in the vervet (Cercopithecus aethiops).

Vervet monkeys (Chlorocebus aethiops) are Old World nonhumans that display attenuated menstruation that requires detection by vaginal swab. The physiology underlying attenuated menstruation in this species has not been previously studied. To fill this gap, we evaluated endometrial cell proliferation, steroid receptor localization and expression of menstruation-associated matrix metalloproteinase (MMP) enzymes in vervets during natural and artificial menstrual cycles.

Injection of antiangiogenic agents into the macaque preovulatory follicle: disruption of corpus luteum development and function.

Ovulation and conversion of the follicle into the corpus luteum involve remarkable changes in vascular permeability and neovascularization of the luteinizing granulosa layer. To evaluate the importance of these vascular events in follicle rupture and luteal development, sequential experiments were designed in which vehicle or angiogenic inhibitors (TNP-470 or angiostatin) were injected directly into the preovulatory follicle of rhesus monkeys during spontaneous menstrual cycles. After control injections, 13 of 14 animals exhibited serum levels of progesterone (P) during the subsequent luteal phase that were comparable to untreated animals in our colony.

Understanding the basis of CD4(+) T-cell depletion in macaques infected by a simian-human immunodeficiency virus.

The efficacy of candidate AIDS vaccines to mediate protection against viral infection and pathogenesis is evaluated, at a preclinical stage, in animal models. One model that is favored because the infecting virus is closely related to HIV-1 and because of the rapidity of pathogenic outcomes is the infection of Old World monkeys by simian-human immunodeficiency virus (SHIV) chimerae. We investigated the basis for the depletion of CD4(+) T lymphocytes in a SHIV-macaque model.