Effects of intracerebroventricular infusions of ghrelin on secretion of follicle-stimulating hormone in peripubertal female sheep

Reproduction depends on mechanisms responsible for the regulation of energy homeostasis and puberty is a developmental period when reproductive and somatic maturity are achieved. Ghrelin affects the activity of the hypothalamo–pituitary–gonadal axis under conditions of energy insufficiency. An in vivo model based on intracerebroventricular (i.c.v.) infusions was used to determine whether centrally administered acyl ghrelin affects transcriptional and translational activity of FSH in peripubertal lambs and whether ghrelin administration mimics the effects of short-term fasting. Standard-fed lambs received either Ringer–Lock (R-L) solution (120 µL h–1) or ghrelin (120 µL h–1, 100 µg day–1). Animals experiencing a short-term (72 h) fast were treated only with R-L solution. In each experimental group, i.c.v. infusions occurred for 3 consecutive days. Immunohistochemistry, in situ hybridisation and real-time reverse transcription quantitative polymerase chain reaction analyses revealed that short-term fasting, as well as exogenous acyl ghrelin administration to standard-fed peripubertal lambs, augmented FSHβ mRNA expression and immunoreactive FSH accumulation. In addition to the effects of ghrelin on FSH synthesis in standard-fed animals, effects on gonadotrophin release were also observed. Acyl ghrelin increased the pulse amplitude for gonadotrophin release, which resulted in an elevation in mean serum FSH concentrations. In conclusion, the present data suggest that ghrelin participates in an endocrine network that modulates gonadotrophic activity in peripubertal female sheep.

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Intercompartmental communication between the cerebrospinal and adjacent spaces during intrathecal infusions in an acute ovine in-vivo model

Fluids and Barriers of the CNS ◽

10.1186/s12987-021-00300-0 ◽

2022 ◽

Vol 19 (1) ◽

Author(s):

Anthony Podgoršak ◽

Nina Eva Trimmel ◽

Markus Florian Oertel ◽

Sara Qvarlander ◽

Margarete Arras ◽

...

Keyword(s):

Constant Pressure ◽

Venous Pressure ◽

Pulse Amplitude ◽

Estimation Methods ◽

In Vivo Model ◽

Mean Pressure ◽

Quantitative Understanding ◽

Pressure Changes ◽

Intrathecal Space

Abstract Introduction The treatment of hydrocephalus has been a topic of intense research ever since the first clinically successful use of a valved cerebrospinal fluid shunt 72 years ago. While ample studies elucidating different phenomena impacting this treatment exist, there are still gaps to be filled. Specifically, how intracranial, intrathecal, arterial, and venous pressures react and communicate with each other simultaneously. Methods An in-vivo sheep trial (n = 6) was conducted to evaluate and quantify the communication existing within the cranio-spinal, arterial, and venous systems (1 kHz sampling frequency). Standardized intrathecal infusion testing was performed using an automated infusion apparatus, including bolus and constant pressure infusions. Bolus infusions entailed six lumbar intrathecal infusions of 2 mL Ringer’s solution. Constant pressure infusions were comprised of six regulated pressure steps of 3.75 mmHg for periods of 7 min each. Mean pressure reactions, pulse amplitude reactions, and outflow resistance were calculated. Results All sheep showed intracranial pressure reactions to acute increases of intrathecal pressure, with four of six sheep showing clear cranio-spinal communication. During bolus infusions, the increases of mean pressure for intrathecal, intracranial, arterial, and venous pressure were 16.6 ± 0.9, 15.4 ± 0.8, 3.9 ± 0.8, and 0.1 ± 0.2 mmHg with corresponding pulse amplitude increases of 2.4 ± 0.3, 1.3 ± 0.3, 1.3 ± 0.3, and 0.2 ± 0.1 mmHg, respectively. During constant pressure infusions, mean increases from baseline were 14.6 ± 3.8, 15.5 ± 4.2, 4.2 ± 8.2, and 3.2 ± 2.4 mmHg with the corresponding pulse amplitude increases of 2.5 ± 3.6, 2.5 ± 3.0, 7.7 ± 4.3, and 0.7 ± 2.0 mmHg for intrathecal, intracranial, arterial, and venous pulse amplitude, respectively. Outflow resistances were calculated as 51.6 ± 7.8 and 77.8 ± 14.5 mmHg/mL/min for the bolus and constant pressure infusion methods, respectively—showing deviations between the two estimation methods. Conclusions Standardized infusion tests with multi-compartmental pressure recordings in sheep have helped capture distinct reactions between the intrathecal, intracranial, arterial, and venous systems. Volumetric pressure changes in the intrathecal space have been shown to propagate to the intraventricular and arterial systems in our sample, and to the venous side in individual cases. These results represent an important step into achieving a more complete quantitative understanding of how an acute rise in intrathecal pressure can propagate and influence other systems.

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A short-term in vivo model for giant cell tumor of bone

BMC Cancer ◽

10.1186/1471-2407-11-241 ◽

2011 ◽

Vol 11 (1) ◽

Cited By ~ 34

Author(s):

Maurice Balke ◽

Anna Neumann ◽

Károly Szuhai ◽

Konstantin Agelopoulos ◽

Christian August ◽

...

Keyword(s):

Giant Cell Tumor ◽

Giant Cell ◽

Cell Tumor ◽

In Vivo Model ◽

Short Term

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An In Vivo Model for Short-Term Evaluation of the Implantation Effects of Biomolecules or Stem Cells in the Dental Pulp

The Open Dentistry Journal ◽

10.2174/1874210600802010067 ◽

2008 ◽

Vol 2 (1) ◽

pp. 67-72 ◽

Cited By ~ 2

Author(s):

Sally Lacerda-Pinheiro ◽

Arnaud Marchadier ◽

Patricio Donas ◽

Dominique Septier ◽

Laurent Benhamou ◽

...

Keyword(s):

Stem Cells ◽

Dental Pulp ◽

In Vivo Model ◽

Short Term ◽

Short Term Evaluation ◽

Term Evaluation

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A hydrosilver gel for plaque control in adults affected by chronic periodontitis: Effects on the ‘red complex’ bacterial load. A prospective longitudinal pilot study using polymerase chain reaction analysis

International Journal of Immunopathology and Pharmacology ◽

10.1177/2058738418825212 ◽

2019 ◽

Vol 33 ◽

pp. 205873841882521

Author(s):

Dorina Lauritano ◽

Alessandro Nota ◽

Marcella Martinelli ◽

Marco Severino ◽

Michele Romano ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Chronic Periodontitis ◽

In Vivo Model ◽

Chain Reaction ◽

Short Term ◽

Significant Difference ◽

Polymerase Chain ◽

Prospective Longitudinal ◽

At Home

In subjects affected by chronic periodontitis, the chemical control of plaque is a strategy aiming primarily at controlling infection and bacterial loading. The aim is to evaluate the bacterial loading of the so-called ‘red complex’ associated with a short-term use of a hydrosilver gel (HSG) by using an in vivo model in adult subjects affected by chronic periodontitis. This prospective short-term clinical trial involved 10 adult volunteers using a 15-day in vivo model. After receiving professional prophylaxis at baseline (t0), each volunteer performed daily applications of HSG at home. After 15 days (t1) from the first application, subgingival plaque samples were collected, and the bacterial loading of species belonging to the red complex was evaluated using polymerase chain reaction (PCR) analyses. The bacterial loading of the red complex showed no statistically significant difference between t0 and t1, although it tended to decrease. HSG can be used at home as an adjunct to domestic oral care because it seems a promising tool, but further studies are needed to involve a larger sample and a longer follow-up.

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