Rabbit Fetal Tissue Research Articles

Vitrification and rapid freezing of rabbit fetal tissues and skin samples from rabbits and pigs

Vitrification (3.58 M EG and 2.82 M DMSO in PBS with 20% FCS) and rapid-freezing (0.25 M sucrose, 2.25 M EG, and 2.25 M DMSO in PBS with 20% FCS) procedures were assayed to cryopreserve rabbit tissue samples from 12-day fetuses, and skin samples from live born pups and adult rabbits. These methods were also assayed to cryopreserve pig skin samples obtained from abattoir animals. The ability of rabbit tissue samples to attach and colonize the substratum by cell proliferation was not affected by the assayed cryopreservation procedures, regardless of specimen age. In porcines, sample attachment and cell proliferation capability of primary cultures were not affected by applied cryopreservation procedures. Almost all primary cultures from cryopreserved skin samples reached confluency (from 92 to 100%). Results reported here allow us to establish in both species, rabbit and pig, a cryobank of skin samples from adult specimens classified as outliers for longevity (in rabbits) and prolificacy (in pigs).

Quantification of methylphenidate (Ritalin®) in rabbit fetal tissue using a chiral liquid chromatography/tandem mass spectrometry assay

Quantification of methylphenidate (Ritalin^®) in rabbit fetal tissue using a chiral liquid chromatography/tandem mass spectrometry assay

Isolation of type II epithelial cells from rabbit fetal lungs by adherence on an IgG-coated surface.

The lung is comprised of about 40 different cell types, of which only 15% are type II cells. These are the major, if not the sole, source of synthesis and secretion of lung surfactant. To date a large number of methods have been described for the isolation of pure populations of type II cells using a wide variety of techniques, but most of these have employed differential centrifugation methods and have used adult rodents. The present study reports the isolation of type II cells from fetal rabbit lungs by the immunoglobin G plating method. Pure populations of fetal type II cells in high yield and with good viability were obtained by the procedure for the first time from rabbit fetal tissue.

Development of the response of rabbit fetal tissues to thyroxine

Development of rabbit fetal tissues sensitivity to thyroxin was studied on the basis of changes in alpha-glycerophosphate oxidase activity in the liver mitochondria of pregnant rabbits and their fetuses to which thyroxin was administered at different stages of pregnancy. T4 administration up to the 23rd day of gestation caused an increase in the enzyme activity in the maternal liver mitochondria only, whereas in the fetus it was at the control level. From the 24th day of pregnancy an increase of the alpha-glycerophosphate oxidase activity was seen in the fetal liver mitochondria. This can be explained by the appearance of rabbit fetal tissues sensitivity to maternal thyroxin at this period of gestation, increasing by the end of pregnancy.

Metabolism of [ 3H]epinephrine in rabbit fetal tissues

[ 3H]epinephrine was injected into rabbit fetuses through the uterine wall on day 26 of gestation and its metabolism was studied in fetal tissues. [ 14C]metanephrine (MN) was synthesized using a soluble rat liver preparation and it, along with [ 14C]epinephrine, was used as recovery markers for the quantitation of metabolites of [ 3H]epinephrine. The radiochemical purity of MN, the predominant metabolite isolated from the fetal liver, was achieved by obtaining a constant [ 3H]/[ 14C] after sequential thin-layer chromatography. Thirty min after the injection of labeled hormone. [ 3H]epinephrine comprised 25 per cent of the radioactivity in the serum and 30 per cent in the heart, while less than 5 per cent was found in the lung, liver, kidney and intestine. Unconjugated MN comprised 45 per cent of the [ 3H] in the serum, 63 per cent in the heart and lung and 47, 46 and 40 per cent in the liver, kidney and intestine respectively. Conjugated MN is only found in liver, kidney and intestine and accounts for 35–40 per cent of the tissue radioactivity. Enzymatic hydrolysis of conjugates with β-glucuronidase in the presence and absence of sulfatase indicates that MN is present as a glucuronide conjugate. O-methylated, deaminated metabolites accounted for 27 per cent of the radioactivity in the serum, 28 per cent in the lung and between 7 and 16 per cent in the heart, liver, kidney and intestine. Thus, in the fetal rabbit, O-methylation is the predominant route of metabolism of injected [ 3H]epinephrine, followed by extensive glucuronide conjugation in the fetal liver, kidney and intestine.

Oxygen consumption in fetal rabbit ductus arteriosus (38590).

Oxygen consumption in fetal rabbit ductus arteriosus and descending aorta was studied after human umbilical artery tissue was used to standardize the technique. A steady state of oxygen consjmption persisted for 90-100 min after dissection, and a tissue dry weight of greater than 15 mg was necessary to obtain reliable data, necessitating pooling of rabbit fetal tissue from 25.75-26.5 day gestation had an oxygen consumption of 2.05 plus or minus 0.22 (4) mul oxygen/10 mg dry wt/hr, and at 27.5-29.5 it was 5.69 plus or minus 0.28 (7) (P less than 0.001). There was no change with gestational age in the oxygen consumption in the descending aorta (2.15 plus or minus 0.23 mul oxygen/10 mg dry wt/hr).