Salt-taste responsivity in Long-Evans rats and Egyptian spiny mice treated with hydrochlorothiazide

In Exp. 1 6 adult male Long-Evans derived rats ( Rattus norvegicus) and 6 adult male spiny mice ( Acomys cahirinus) were observed individually inside a 60-cm × 30-cm × 30-cm open field during a 15-min. session. Measures of locomotion, immobility, self-grooming, rearing-up, and object contact were obtained. Tests of species differences indicated that spiny mice showed significantly more locomotor and rearing behavior than Norway rats. In Exp. 2 12 adult Norway rats (6 male, 6 female) and 12 adult spiny mice (6 male, 6 female) were observed individually inside a six-compartment maze during a 15-min. session. Although no sex difference in maze exploration was found, spiny mice showed significantly more maze exploration than Norway rats. These results suggest that spiny mice, highly precocial in development relative to Norway rats, exhibit correlates of that neonatal competence as adults evidenced by greater behavioral activity and locomotor exploration in novel environments.

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Conditioned Taste Aversions and Latent Inhibition in Egyptian Spiny Mice and Long-Evans Rats

Perceptual and Motor Skills ◽

10.2466/pms.1995.80.3.995 ◽

1995 ◽

Vol 80 (3) ◽

pp. 995-998

Author(s):

Gary M. Brosvic ◽

Pamela Hartsell ◽

Jill Spruill ◽

Mary Correla ◽

Patricia Long ◽

...

Keyword(s):

Taste Aversion ◽

Latent Inhibition ◽

Conditioned Taste Aversion ◽

Double Blind ◽

First Report ◽

Spiny Mice ◽

Control Procedures ◽

Long Evans

The acquisition and extinction of a conditioned taste aversion in Egyptian spiny mice and Long-Evans rats was compared during 20 posttest sessions using a cross-over design and double-blind control procedures. Spiny mice preexposed to a sucrose CS demonstrated more latent inhibition and a faster rate of extinction than did Long-Evans rats preexposed to the same CS. Preference indices did not differ between control animals or as a function of gender. The present results are the first report of the effects of latent inhibition on learning taste aversion in Egyptian spiny mice.

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Ultrastructural Investigation of Spontaneous Pituitary Adenomas in Aging Sprague-Dawley Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053747 ◽

1982 ◽

Vol 40 ◽

pp. 216-217

Author(s):

D. J. McComb ◽

J. Beri ◽

F. Zak ◽

K. Kovacs

Keyword(s):

Microscopic Study ◽

Pituitary Adenomas ◽

Wistar Rats ◽

Microscopic Level ◽

Sprague Dawley ◽

Prolactin Cells ◽

Light Microscopic Level ◽

Ultrastructural Investigation ◽

Sprague Dawley Rats ◽

Long Evans

Investigation of the spontaneous pituitary adenomas in rat have been limited mainly to light microscopic study. Furth et al. (1973) described them as chromophobic, secreting prolactin. Kovacs et al. (1977) in an ul trastructural investigation of adenomas of old female Long-Evans rats, found that they were composed of prolactin cells. Berkvens et al. (1980) using immunocytochemistry at the light microscopic level, demonstrated that some spontaneous tumors of old Wistar rats could contain GH, TSH or ACTH as well as PRL.

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The effect of bromocriptine on mammary-gland ultrastructure of hyperprolactinemic rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111136 ◽

1984 ◽

Vol 42 ◽

pp. 204-205

Author(s):

I.C. Murray

Keyword(s):

Mammary Gland ◽

Dopamine Agonist ◽

Alveolar Epithelium ◽

Mammary Glands ◽

Female Rats ◽

Control Group ◽

Cell Hyperplasia ◽

Once Daily ◽

Long Evans

In women, hyperprolactinemia is often due to a prolactin (PRL)-secreting adenoma or PRL cell hyperplasia. RRL excess stimulates the mammary glands and causes proliferation of the alveolar epithelium. Bromocriptine, a dopamine agonist, inhibits PRL secretion and is given to women to treat nonpuerperal galactorrhea. Old female rats have been reported to have PRL cell hyperplasia or adenoma leading to PRL hypersecretion and breast stimulation. Herein, we describe the effect of bromocriptine and consequently the reduction in serum PRL levels on the ultrastructure of rat mammary glands.Female Long-Evans rats, 23 months of age, were divided into control and bromocriptine-treated groups. The control animals were injected subcutaneously once daily with a 10% ethanol vehicle and were later divided into a normoprolactinemic control group with serum PRL levels under 30 ng/ml and a hyperprolactinemic control group with serum PRL levels above 30 ng/ml.

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