Genetic Deletion of the Prostaglandin EP3 Receptor in the Kidney Tubule of Adult Mice Has No Impact on Kidney Water Handling

(1) Background: The c-Jun-NH2-terminal protein kinase (JNK) is a mitogen-activated protein kinase involved in regulating physiological processes in the central nervous system. However, the dual genetic deletion of Mkk4 and Mkk7 (upstream activators of JNK) in adult mice is not reported. The aim of this study was to induce the genetic deletion of Mkk4/Mkk7 in adult mice and analyze their effect in hippocampal neurogenesis. (2) Methods: To achieve this goal, Actin-CreERT2 (Cre+/−), Mkk4flox/flox, Mkk7flox/flox mice were created. The administration of tamoxifen in these 2-month-old mice induced the gene deletion (Actin-CreERT2 (Cre+/−), Mkk4∆/∆, Mkk7∆/∆ genotype), which was verified by PCR, Western blot, and immunohistochemistry techniques. (3) Results: The levels of MKK4/MKK7 at 7 and 14 days after tamoxifen administration were not eliminated totally in CNS, unlike what happens in the liver and heart. These data could be correlated with the high levels of these proteins in CNS. In the hippocampus, the deletion of Mkk4/Mkk7 induced a misalignment position of immature hippocampal neurons together with alterations in their dendritic architecture pattern and maturation process jointly to the diminution of JNK phosphorylation. (4) Conclusion: All these data supported that the MKK4/MKK7–JNK pathway has a role in adult neurogenic activity.

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Different Roles for VIP Neurons in the Neonatal and Adult Suprachiasmatic Nucleus

Journal of Biological Rhythms ◽

10.1177/0748730420932073 ◽

2020 ◽

Vol 35 (5) ◽

pp. 465-475 ◽

Cited By ~ 1

Author(s):

Cristina Mazuski ◽

Samantha P. Chen ◽

Erik D. Herzog

Keyword(s):

Suprachiasmatic Nucleus ◽

Daily Activity ◽

Locomotor Behavior ◽

Circadian Period ◽

Circadian Gene ◽

Daily Rhythms ◽

Apoptotic Pathway ◽

Adult Mice ◽

Genetic Deletion

The suprachiasmatic nucleus (SCN) drives circadian rhythms in locomotion through coupled, single-cell oscillations. Global genetic deletion of the neuropeptide Vip or its receptor Vipr2 results in profound deficits in daily synchrony among SCN cells and daily rhythms in locomotor behavior and glucocorticoid secretion. To test whether this phenotype depends on vasoactive intestinal polypeptide (VIP) neurons in the SCN, we ablated VIP SCN neurons in vivo in adult male mice through Caspase3-mediated induction of the apoptotic pathway in cre-expressing VIP neurons. We found that ablation of VIP SCN neurons in adult mice caused a phenotype distinct from Vip- and Vipr2-null mice. Mice lacking VIP neurons retained rhythmic locomotor activity with a shortened circadian period, more variable onsets, and decreased duration of daily activity. Circadian hormonal outputs, specifically corticosterone rhythms, were severely dampened. In contrast, deletion of neonatal SCN VIP neurons dramatically reduced circadian gene expression in the cultured SCN, mimicking the effects of global deletion of Vip or Vipr2. These results suggest that SCN VIP neurons play a role in lengthening circadian period and stimulating the daily surge in glucocorticoids in adults and in synchronizing and sustaining daily rhythms among cells in the developing SCN.

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Genetic Deletion of Catalytic Subunits of AMP-activated Protein Kinase Increases Osteoclasts and Reduces Bone Mass in Young Adult Mice

Journal of Biological Chemistry ◽

10.1074/jbc.m112.430389 ◽

2013 ◽

Vol 288 (17) ◽

pp. 12187-12196 ◽

Cited By ~ 34

Author(s):

Heeseog Kang ◽

Benoit Viollet ◽

Dianqing Wu

Keyword(s):

Young Adult ◽

Protein Kinase ◽

Bone Mass ◽

Catalytic Subunits ◽

Adult Mice ◽

Genetic Deletion ◽

Amp Activated Protein Kinase

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Genetic deletion of catalytic subunits of AMP-activated protein kinase increases osteoclasts and reduces bone mass in young adult mice.

Journal of Biological Chemistry ◽

10.1074/jbc.a112.430389 ◽

2013 ◽

Vol 288 (32) ◽

pp. 23432-23432

Author(s):

Heeseog Kang ◽

Benoit Viollet ◽

Dianqing Wu

Keyword(s):

Young Adult ◽

Protein Kinase ◽

Bone Mass ◽

Catalytic Subunits ◽

Adult Mice ◽

Genetic Deletion ◽

Amp Activated Protein Kinase

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Adult mice lacking VIP SCN neurons retain circadian locomotor behavior but exhibit dampened daily glucocorticoid rhythms

10.1101/2020.01.07.897140 ◽

2020 ◽

Author(s):

Cristina Mazuski ◽

Samantha P. Chen ◽

Erik D. Herzog

Keyword(s):

Gene Expression ◽

Circadian Rhythms ◽

Daily Activity ◽

Locomotor Behavior ◽

Circadian Period ◽

Circadian Gene ◽

Daily Rhythms ◽

Apoptotic Pathway ◽

Adult Mice ◽

Genetic Deletion

AbstractThe suprachiasmatic nucleus (SCN) drives circadian rhythms in locomotion through coupled, single-cell oscillations. Global genetic deletion of the neuropeptide, Vip or its receptor Vipr2, results in profound deficits in daily synchrony among SCN cells and daily rhythms in locomotor behavior and glucocorticoid secretion. To test whether this phenotype depends on VIP neurons in the SCN, we ablated VIP SCN neurons in vivo in adult mice through Caspase3-mediated induction of the apoptotic pathway in cre-expressing VIP neurons. We found that ablation of VIP SCN neurons in adult mice caused a phenotype distinct from Vip- and Vipr2- null mice. Mice lacking VIP neurons retained rhythmic locomotor activity with a shortened circadian period, more variable onsets and decreased duration of daily activity. Circadian hormonal outputs, specifically corticosterone rhythms were severely dampened. In contrast, deletion of neonatal SCN VIP neurons dramatically reduced circadian gene expression in the cultured SCN, mimicking the effects of global deletion of Vip or Vipr2. These results suggest that SCN VIP neurons play a role in lengthening circadian period and stimulating the daily surge in glucocorticoids in adults and in synchronizing and sustaining daily rhythms among cells in the developing SCN.Significance StatementThe importance of the neuropeptide, VIP, for circadian rhythms has been described in mice lacking the gene for Vip or its receptor, Vipr2. This study found that ablation of VIP neurons only in the adult SCN reproduced the loss of circadian rhythms in glucocorticoids, but not the loss of circadian locomotor behavior, seen with global loss of VIP signaling. We conclude that VIP SCN neurons play two roles: one in adulthood lengthening circadian period and regulating circadian outputs, and one in development coordinating synchrony among circadian cells.

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Binucleate Spermiogenesis in the Mouse

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009381x ◽

1972 ◽

Vol 30 ◽

pp. 112-113

Author(s):

John J. Wolosewick

Keyword(s):

Electron Microscopy ◽

Phosphate Buffer ◽

Seminiferous Epithelium ◽

Mouse Testis ◽

Germinal Epithelium ◽

Intercellular Bridges ◽

Adult Mice ◽

Cervical Dislocation ◽

Human And Mouse

Classically, the male germinal epithelium is depicted as synchronously developing uninucleate spermatids conjoined by intercellular bridges. Recently, binucleate and multinucleate spermatids from human and mouse testis have been reported. The present paper describes certain developmental events in one type of binucleate spermatid in the seminiferous epithelium of the mouse.Testes of adult mice (ABP Jax) were removed from the animals after cervical dislocation and placed into 2.5% glutaraldehyde/Millonig's phosphate buffer (pH 7.2). Testicular capsules were gently split and separated, exposing the tubules. After 15 minutes the tissue was carefully cut into cubes (approx. 1mm), fixed for an additional 45 minutes and processed for electron microscopy.

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Ineffective Thrombopoiesis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158881 ◽

1990 ◽

Vol 48 (3) ◽

pp. 266-267

Author(s):

JM Radley ◽

SL Ellis

Keyword(s):

Microscopic Examination ◽

Phosphate Buffer ◽

Primary Myelofibrosis ◽

Transient Increase ◽

Major Difficulty ◽

Adult Mice ◽

Dense Cytoplasm

In effective thrombopoies is has been inferred to occur in several disease sates from considerations of megakaryocyte mass and platelet kinetics. Microscopic examination has demonstrated increased numbers of megakaryocytes, with a typical forms particularly pronounced, in primary myelofibrosis. It has not been documented if megakaryocyte ever fail to reach maturity in non-pathological situations. A major difficulty of establishing this is that the number of megakaryocytes normally present in the marrow is extremely low. A large transient increase in megakaryocytopoiesis can how ever be induced in mice by an injection of 5-fluorouracil. We have utilised this treatment and report here evidence for in effective thrombopoies is in healthy mice.Adult mice were perfused (2% glutaraldehyde in 0.08M phosphate buffer, pH 7.4) 8 days following an injection of 5-fluorouracil (150mg/kg). Femurs were subsequently decalcified in 10% neutral E.D.T.A. and embedded in Spurrs resin. Transverse sections of marrow revealed many megakaryocytes at various stages of maturity. Occasional megakaryocytes (less than 1%) were found to be under going degeneration prior to achieving full maturation and releasing cytoplasm as platelets. These cells were characterized by a peripheral rim of dense cytoplasm which enveloped a mass of organelles and vacuoles (Fig. 1). Numerous microtubules were foundaround and with in the organelle-rich zone (Fig 2).

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