Cortical evolution 2018: Advantages of animal model species

Most biomedical neuroscientists realize the importance of the study of brain evolution to help them understand the differences and similarities between their animal model of choice and the human brains in which they are ultimately interested. Many think of evolution as a linear process, going from simpler brains, as those of rats, to more complex ones, as those of humans. However, in reality, every extant species' brain has undergone as long a period of evolution as has the human brain, and each brain has its own species-specific adaptations. By understanding the variety of existing brain types, we can more accurately reconstruct the brains of common ancestors, and understand which brain traits (of humans as well as other species) are derived and which are ancestral. This understanding also allows us to identify convergently evolved traits, which are crucial in formulating hypotheses about structure–function relationships in the brain. A thorough understanding of the processes and patterns of brain evolution is essential to generalizing findings from ‘model species’ to humans, which is the backbone of modern biomedical science.

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Word learning dogs (Canis familiaris) provide an animal model for studying exceptional performance

Scientific Reports ◽

10.1038/s41598-021-93581-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Claudia Fugazza ◽

Shany Dror ◽

Andrea Sommese ◽

Andrea Temesi ◽

Ádám Miklósi

Keyword(s):

Animal Model ◽

Word Learning ◽

Human Activities ◽

Canis Familiaris ◽

Learning Object ◽

Superior Performance ◽

Model Species ◽

Qualitative Variation ◽

Choice Tests ◽

Previous Training

AbstractExceptional performance is present in various human activities but its origins are debated and challenging to study. We report evidence of exceptional performance and qualitative variation in learning object-names in dogs. 34 naïve family dogs and 6 knowledgeable individuals that knew multiple toy names, found in 2 years of search around the Globe, were exposed to 3 months of training to learn two novel toy-names and were tested in two-way choice tests. Only 1 naïve and all 6 knowledgeable dogs passed the tests. Additionally, only these dogs learned at least 10 new toy names over the 3 months, showing qualitative variation in this capacity. Although previous object-name knowledge could provide an explanation for the superior performance of the knowledgeable dogs, their rarity and the absence of previous training of this skill point to exceptional giftedness in these individuals, providing the basis to establish dogs as a model-species for studying talent.

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Ultrastructural investigation of spontaneous pituitary gonadotroph cell adenomas in aging Sprague-Dawley rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077086 ◽

1983 ◽

Vol 41 ◽

pp. 702-703

Author(s):

D. J. McComb ◽

J. Beri ◽

F. Zak ◽

K. Kovacs

Keyword(s):

Electron Microscopy ◽

Animal Model ◽

Epoxy Resin ◽

Immunoelectron Microscopy ◽

Tumor Type ◽

Gonadal Function ◽

Sprague Dawley ◽

Male And Female ◽

Reticulin Fibers ◽

Sprague Dawley Rats

Gonadotroph cell adenomas of the pituitary are infrequent in human patients and are not invariably associated with altered gonadal function. To date, no animal model of this tumor type exists. Herein, we describe spontaneous gonadotroph cell adenomas in old male and female Sprague-Dawley rats by histology, immunocytology and electron microscopy.The material consisted of the pituitaries of 27 male and 38 female Sprague Dawley rats, all 26 months of age or older, removed at routine autopsy. Sections of formal in-fixed, paraffin-embedded tissue were stained with hematoxylin-phloxine-saffron (HPS), the PAS method and the Gordon-Sweet technique for the demonstration of reticulin fibers. For immunostaining, sections were exposed to anti-rat β-LH, anti-ratβ-TSH, anti-rat PRL, anti-rat GH and anti-rat ACTH 1-39. For electron microscopy, tissue was fixed in 2.5% glutaraldehyde, postfixed in 1% OsO4 and embedded in epoxy-resin. Tissue fixed in 10% formalin, embedded in epoxy resin without osmification, was used for immunoelectron microscopy.

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Electron Microscopic Detection and Characterization of Nonhuman Primate Enteric Viruses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054145 ◽

1982 ◽

Vol 40 ◽

pp. 306-307

Author(s):

G. C. Smith ◽

R. L. Heberling ◽

S. S. Kalter

Keyword(s):

Electron Microscopy ◽

Animal Model ◽

Nonhuman Primate ◽

Clinical Condition ◽

Intestinal Tract ◽

Enteric Viruses ◽

Electron Microscopic ◽

Microscopic Detection

A number of viral agents are recognized as and suspected of causing the clinical condition “gastroenteritis.” In our attempts to establish an animal model for studies of this entity, we have been examining the nonhuman primate to ascertain what viruses may be found in the intestinal tract of “normal” animals as well as animals with diarrhea. Several virus types including coronavirus, adenovirus, herpesvirus, and picornavirus (Table I) were detected in our colony; however, rotavirus, astrovirus, and calicivirus have not yet been observed. Fecal specimens were prepared for electron microscopy by procedures reported previously.

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Neurofilaments and Paired Helical Filaments

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120357 ◽

1985 ◽

Vol 43 ◽

pp. 740-743

Author(s):

J. Metuzals

Keyword(s):

Animal Model ◽

Posttranslational Modifications ◽

Posttranslational Modification ◽

Giant Axon ◽

Paired Helical Filaments ◽

Squid Giant Axon ◽

In Vitro Experiments ◽

Thin Sections ◽

Structural Relationships

It has been demonstrated that the neurofibrillary tangles in biopsies of Alzheimer patients, composed of typical paired helical filaments (PHF), consist also of typical neurofilaments (NF) and 15nm wide filaments. Close structural relationships, and even continuity between NF and PHF, have been observed. In this paper, such relationships are investigated from the standpoint that the PHF are formed through posttranslational modifications of NF. To investigate the validity of the posttranslational modification hypothesis of PHF formation, we have identified in thin sections from frontal lobe biopsies of Alzheimer patients all existing conformations of NF and PHF and ordered these conformations in a hypothetical sequence. However, only experiments with animal model preparations will prove or disprove the validity of the interpretations of static structural observations made on patients. For this purpose, the results of in vitro experiments with the squid giant axon preparations are compared with those obtained from human patients. This approach is essential in discovering etiological factors of Alzheimer's disease and its early diagnosis.

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Membrane-associated microtubular areays induced in proximal myelinated processes of dorsal root ganglia by large doses of vitamin B6

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143468 ◽

1986 ◽

Vol 44 ◽

pp. 368-369

Author(s):

V.J. Montpetit ◽

S. Dancea ◽

L. Tryphonas ◽

D.F. Clapin

Keyword(s):

Animal Model ◽

Endoplasmic Reticulum ◽

Dorsal Root Ganglia ◽

Rough Endoplasmic Reticulum ◽

Dorsal Root ◽

Vitamin B6 ◽

Morphological Changes ◽

Model System ◽

Sensory Nerves ◽

Peripheral Sensory

Very large doses of pyridoxine (vitamin B6) are neurotoxic in humans, selectively affecting the peripheral sensory nerves. We have undertaken a study of the morphological and biochemical aspects of pyridoxine neurotoxicity in an animal model system. Early morphological changes in dorsal root ganglia (DRG) associated with pyridoxine megadoses include proliferation of neurofilaments, ribosomes, rough endoplasmic reticulum, and Golgi complexes. We present in this report evidence of the formation of unique aggregates of microtubules and membranes in the proximal processes of DRG which are induced by high levels of pyridoxine.

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Paired helical filaments (PHF) in rats: An experimental animal model for Alzheimer's disease

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128493 ◽

1987 ◽

Vol 45 ◽

pp. 842-843

Author(s):

V.J.A. Montpetit ◽

S. Dancea ◽

S.W. French ◽

D.F. Clapin

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Animal Model ◽

Paired Helical Filaments ◽

Ethanol Intoxication ◽

Drg Neurons ◽

Critical Difference ◽

Suitable Animal Model ◽

The Central Nervous System ◽

Chronic Ethanol Intoxication

A continuing problem in Alzheimer research is the lack of a suitable animal model for the disease. The absence of neurofibrillary tangles of paired helical filaments is the most critical difference in the processes by which the central nervous system ages in most species other than man. However, restricting consideration to single phenomena, one may identify animal models for specific aspects of Alzheimer's disease. Abnormal fibers resembling PHF have been observed in dorsal root ganglia (DRG) neurons of rats in a study of chronic ethanol intoxication and spontaneously in aged rats. We present in this report evidence that PHF-like filaments occur in ethanol-treated rats of young age. In control animals lesions similar in some respects to our observations of cytoskeletal pathology in pyridoxine induced neurotoxicity were observed.Male Wistar BR rats (Charles River Labs) weighing 350 to 400 g, were implanted with a single gastrostomy cannula and infused with a liquid diet containing 30% of total calories as fat plus ethanol or isocaloric dextrose.

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