Biomedical subjects

J Hukkanen

Publications and source records attributed to J Hukkanen.

21 records · Page 2Linked to original sources

PubMed1987

Reabsorption of solutes and water from fluid-filled rabbit lungs.

Uncertainty persists concerning the mechanisms responsible for fluid clearance from the lungs after the air spaces become flooded in severe pulmonary edema. In this study, solute and water fluxes were investigated in an isolated, fluid-filled, perfused rabbit lung preparation. These lungs were perfused with physiologic 1.0 or 5.0 g/dl albumin solutions, and the air spaces were flushed and filled with the same solutions. Samples were obtained at intervals from the perfusate, and at the end of 1 or 2 h, fluid was pumped from the trachea into collection tubes. Concentrations of albumin (labeled with Evans blue) in the air space increased by 2.4 +/- 0.7% (SEM) at 1 h and by 7.0 +/- 0.8% at 2 h. Approximately half of the increase at 2 h could be attributed to dehydration (as judged by increases in perfusate and air-space Na+ concentration). Because previous studies have indicated that the movement of labeled protein between these compartments is very slow in this preparation, it can be concluded that fluid is being reabsorbed from the air spaces. However, reabsorption appears to be slower in rabbits than in rats and it is not stimulated by terbutaline, an effect observed in other species. Under control conditions, potassium concentrations in the air-space fluid fell from 4.01 +/- 0.05 (SEM) mEq/L to 3.37 +/- 0.14 mEq/L at 1 h. Concentrations of K+ in the perfusate rose during this interval from 3.95 +/- 0.05 mEq/L to 4.39 +/- 0.08 mEq/L.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗

PubMed1986

Movement of ions and small solutes across endothelium and epithelium of perfused rabbit lungs.

In situ and isolated fluid-filled rabbit lungs were used to study the transport of indicators between the air space and vascular compartments. These indicators were placed in either the perfusate or air spaces and samples were collected from the perfusate at intervals during a 1-h perfusion period. At the end of the hour, fluid was pumped out of the air space compartment into serial tubes and indicator concentrations were determined in both the air space and perfusion fluids. One hour after introducing the indicators into the air space, the relative decreases in solute concentration were (arranged from the greatest to the least decline): [14C]urea greater than 36Cl- = 125I- greater than 22Na+ greater than [3H]mannitol. The relative rates at which the indicators appeared in the perfusate were similar. When the indicators were placed in the perfusate, a similar relationship was observed in the increase in air space concentrations, but the loss of 22Na+ from the perfusate was similar to those of 36Cl- and 125I-. Losses of all indicators from the perfusate were two or more times those from the air spaces, and although the loss of [3H]mannitol from the perfusate was similar to that of 22Na+ for about 30 min, subsequent loss was much slower. Very little 125I-albumin traversed the tissue barrier, and the small changes in the concentrations of 125I-albumin in the air spaces suggested that little fluid movement had occurred. These studies suggest that the epithelium is less permeable to solutes than the endothelium and permits passage of anions at a faster rate than 22Na+.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1983

Experimental hematogenous endophthalmitis due to Cryptococcus neoformans.

New Zealand white female rabbits injected with 6 X 10(7) to 5.5 X 10(8) CFU of Cryptococcus neoformans into the right carotid artery developed three types of clinically detectable eye lesions. These eye manifestations included: (1) iritis that had distinctive 1-3 mm white nodules; (2) white vitreous lesions with ill-defined borders, and (3) focal and diffusely infiltrative lesions of the optic nerve radiations. Most of the eye lesions appeared between 1 to 3 weeks after intracarotid injection and resolved almost completely by 10 weeks. Their clinical appearance resembled some of the eye lesions described from human cases. Predominantly a mononuclear leukocyte response with scattered cryptococcal organisms were seen in the iris and optic nerve lesions. Serial quantitative cultures from eye tissues, brain, and kidney indicated that the clearance of viable cryptococci was slowest from the eye tissues. Among the three diagnostic techniques (India Ink mount, culture, and cryptococcal polysaccharide antigen (CPA) determination), the CPA determination was the most sensitive test to detect C. neoformans in the aqueous and vitreous humors of clinically involved eyes. This rabbit model may be useful for further studies on hematogenous cryptococcal endophthalmitis.

Animals↗